| Schedule of investments |
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Gross Unrealized
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Losses
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Amortized
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Less than
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Greater than
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Estimated
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Cost
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Gains
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One Year
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One Year
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Fair Value
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(In thousands)
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March 31, 2015
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Short-term investments:
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Available-for-sale securities:
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U.S. government and agency debt securities
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$
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310,469
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$
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353
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$
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(10)
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$
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—
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$
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310,812
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Corporate debt securities
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182,014
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137
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(60)
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—
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182,091
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International government agency debt securities
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45,215
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37
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(4)
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—
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45,248
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Total short-term investments
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537,698
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527
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(74)
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—
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538,151
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Long-term investments:
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Available-for-sale securities:
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Corporate debt securities
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28,001
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—
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(26)
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—
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27,975
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U.S. government and agency debt securities
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26,090
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—
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(6)
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(4)
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26,080
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International government agency debt securities
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2,575
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—
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—
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—
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2,575
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56,666
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—
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(32)
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(4)
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56,630
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Held-to-maturity securities:
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Certificates of deposit
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1,619
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—
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—
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—
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1,619
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Total long-term investments
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58,285
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—
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(32)
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(4)
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58,249
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Total investments
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$
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595,983
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$
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527
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$
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(106)
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$
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(4)
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$
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596,400
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December 31, 2014
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Short-term investments:
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Available-for-sale securities:
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U.S. government and agency debt securities
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$
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226,387
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$
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88
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$
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(15)
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$
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—
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$
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226,460
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Corporate debt securities
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140,900
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26
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(66)
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—
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140,860
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International government agency debt securities
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39,774
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13
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(5)
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—
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39,782
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Total short-term investments
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407,061
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127
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(86)
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—
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407,102
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Long-term investments:
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Available-for-sale securities:
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U.S. government and agency debt securities
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100,429
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—
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(196)
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(40)
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100,193
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Corporate debt securities
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61,187
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—
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(84)
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—
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61,103
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International government agency debt securities
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7,568
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—
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(2)
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(1)
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7,565
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169,184
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—
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(282)
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(41)
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168,861
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Held-to-maturity securities:
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Certificates of deposit
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1,619
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—
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—
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—
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1,619
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Total long-term investments
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170,803
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—
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(282)
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(41)
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170,480
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Total investments
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$
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577,864
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$
|
127
|
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$
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(368)
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$
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(41)
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$
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577,582
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| The cost and fair value of available-for-sale and held-to-maturity securities by contractual maturity |
The Company’s available-for-sale and held-to-maturity securities at March 31, 2015 had contractual maturities in the following periods:
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Available-for-sale
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Held-to-maturity
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Amortized
|
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Estimated
|
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Amortized
|
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Estimated
|
|
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(In thousands)
|
|
Cost
|
|
Fair Value
|
|
Cost
|
|
Fair Value
|
|
|
Within 1 year
|
|
$
|
334,207
|
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$
|
334,234
|
|
$
|
1,619
|
|
$
|
1,619
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|
|
After 1 year through 5 years
|
|
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260,157
|
|
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260,547
|
|
|
—
|
|
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—
|
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Total
|
|
$
|
594,364
|
|
$
|
594,781
|
|
$
|
1,619
|
|
$
|
1,619
|
|
|