| CASH, CASH EQUIVALENTS, AND MARKETABLE SECURITIES |
4.CASH, CASH EQUIVALENTS, AND MARKETABLE SECURITIES
The amortized cost, gross unrealized gains and losses, and fair value of cash, cash equivalents, and marketable securities as of December 31, 2020 and 2019, are as follows (in thousands):
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December 31, 2020
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Cost
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Unrealized
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Unrealized
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Cash and Cash
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Marketable
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Basis
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Gains
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Losses
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Fair Value
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Equivalents
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Securities
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Cash
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$
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709,924
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$
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—
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$
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—
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$
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709,924
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$
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709,924
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$
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—
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Money market funds
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618,197
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—
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—
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618,197
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618,197
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—
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Commercial paper
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81,037
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1
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—
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81,038
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81,038
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—
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Corporate debt securities
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29,891
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26
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(2)
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29,915
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3,506
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26,409
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Asset-backed securities
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12,518
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19
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(4)
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12,533
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—
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12,533
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U.S. agency securities
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6,993
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2
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—
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6,995
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—
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6,995
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U.S. Treasury securities
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1,700
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—
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—
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1,700
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—
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1,700
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Total
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$
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1,460,260
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$
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48
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$
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(6)
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$
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1,460,302
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$
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1,412,665
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$
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47,637
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December 31, 2019
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Cost
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Unrealized
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Unrealized
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Cash and Cash
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Marketable
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Basis
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Gains
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Losses
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Fair Value
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Equivalents
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Securities
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Cash
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$
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366,358
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$
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—
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$
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—
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$
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366,358
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$
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366,358
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$
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—
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Money market funds
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30,935
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—
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—
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30,935
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30,935
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—
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Commercial paper
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19,997
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1
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(4)
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19,994
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7,038
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12,956
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Corporate debt securities
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16,417
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12
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(1)
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16,428
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—
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16,428
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Asset-backed securities
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12,482
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12
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(2)
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12,492
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—
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12,492
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U.S. agency securities
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749
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—
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—
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749
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749
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—
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U.S. Treasury securities
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1,000
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—
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—
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1,000
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—
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1,000
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Non-U.S. securities
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700
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—
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—
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700
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—
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700
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Total
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$
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448,638
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$
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25
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$
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(7)
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$
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448,656
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$
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405,080
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$
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43,576
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A summary of debt securities with unrealized losses aggregated by period of continuous unrealized loss is as follows (in thousands):
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Less than 12 Months
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12 Months or Greater
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Total
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Fair
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Unrealized
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Fair
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Unrealized
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Fair
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Unrealized
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December 31, 2020
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Value
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Losses
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Value
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Losses
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Value
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Losses
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Commercial paper
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$
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19,296
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$
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—
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$
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—
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$
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—
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$
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19,296
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$
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—
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Corporate-debt securities
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7,538
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(2)
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—
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—
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7,538
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(2)
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Asset-backed securities
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4,611
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(4)
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—
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—
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4,611
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(4)
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Total
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$
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31,445
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$
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(6)
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$
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—
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$
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—
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$
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31,445
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$
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(6)
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Less than 12 Months
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12 Months or Greater
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Total
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Fair
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Unrealized
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Fair
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Unrealized
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Fair
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Unrealized
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December 31, 2019
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Value
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Losses
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Value
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Losses
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Value
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Losses
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Commercial paper
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$
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15,059
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$
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(4)
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$
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—
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$
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—
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$
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15,059
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$
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(4)
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Corporate-debt securities
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3,166
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(1)
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—
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—
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3,166
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(1)
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Asset-backed securities
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4,258
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(2)
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—
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—
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4,258
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(2)
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Non-U.S. securities
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700
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—
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—
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—
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700
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—
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Total
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$
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23,183
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$
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(7)
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$
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—
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$
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—
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$
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23,183
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$
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(7)
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The scheduled contractual maturities of debt securities as of December 31, 2019 are as follows (in thousands):
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After
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1 Year
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Within
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through
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December 31, 2020
|
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Fair Value
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1 Year
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5 Years
|
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Commercial paper
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$
|
81,038
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$
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81,038
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$
|
—
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Corporate-debt securities
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29,915
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29,915
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—
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Asset-backed securities
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|
12,533
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12,533
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—
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U.S. agency securities
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6,995
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6,995
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—
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U.S. Treasury securities
|
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1,700
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1,700
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—
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Total
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$
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132,181
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$
|
132,181
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$
|
—
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