| Schedule of Cash, Cash Equivalents and Short-term Investments [Table Text Block] |
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Balance
Sheet Classifications
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Cost
Basis
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Unrealized
Gain
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Unrealized
(Loss)
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Recorded
Basis
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Cash
and Cash Equivalents
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Short-term
Investments
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Cash
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$
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799,108
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$
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—
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$
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—
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$
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799,108
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$
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799,107
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$
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—
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Money
market mutual funds
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63,327
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—
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—
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63,327
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63,327
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—
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Certificates
of deposit
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293,200
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—
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(690
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)
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292,510
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78,997
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213,514
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Available-for-sale
securities:
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Bond
mutual funds
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20,863
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—
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(237
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)
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20,626
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—
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20,626
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Corporate
bonds
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21,366
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86
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(1
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21,451
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—
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21,451
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Total
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$
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1,197,864
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$
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86
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$
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(928
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)
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$
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1,197,022
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$
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941,431
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$
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255,591
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Balance
Sheet Classifications
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Cost
Basis
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Unrealized
Gain
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Unrealized
(Loss)
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Recorded
Basis
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Cash
and Cash Equivalents
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Short-term
Investments
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Cash
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$
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932,628
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$
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—
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$
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—
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$
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932,628
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$
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932,628
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$
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—
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Money
market mutual funds
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154,982
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—
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—
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154,982
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154,982
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—
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Certificates
of deposit
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257,766
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—
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—
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257,766
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4,273
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253,493
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Available-for-sale
securities:
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Bond
mutual funds
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20,734
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—
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(69
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20,665
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—
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20,665
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Corporate
bonds
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22,537
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46
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(9
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22,574
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—
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22,574
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Total
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$
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1,388,647
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$
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46
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$
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(78
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$
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1,388,615
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$
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1,091,883
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$
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296,732
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