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Cash, Cash Equivalents, and Investments - Summary of Available-for-Sale Investments (Detail) $ in Thousands | Mar. 31, 2019 USD ($)
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Debt Securities, Available-for-sale [Line Items] |
Amortized cost | $ 757,843
Gross unrealized gains | 1,253
Gross unrealized losses | (705)
Fair value | 758,391
Treasury bills |
Debt Securities, Available-for-sale [Line Items] |
Gross unrealized losses | (23)
Treasury bills | Short-Term Investments |
Debt Securities, Available-for-sale [Line Items] |
Amortized cost | 189,599
Gross unrealized gains | 211
Gross unrealized losses | (2)
Fair value | 189,808
Treasury bills | Long-Term Investments |
Debt Securities, Available-for-sale [Line Items] |
Amortized cost | 104,987
Gross unrealized gains | 332
Gross unrealized losses | (21)
Fair value | 105,298
Corporate bonds |
Debt Securities, Available-for-sale [Line Items] |
Gross unrealized losses | (505)
Corporate bonds | Short-Term Investments |
Debt Securities, Available-for-sale [Line Items] |
Amortized cost | 137,294
Gross unrealized gains | 87
Gross unrealized losses | (153)
Fair value | 137,228
Corporate bonds | Long-Term Investments |
Debt Securities, Available-for-sale [Line Items] |
Amortized cost | 152,668
Gross unrealized gains | 329
Gross unrealized losses | (352)
Fair value | 152,645
Asset-backed securities |
Debt Securities, Available-for-sale [Line Items] |
Gross unrealized losses | (139)
Asset-backed securities | Short-Term Investments |
Debt Securities, Available-for-sale [Line Items] |
Amortized cost | 98,902
Gross unrealized gains | 135
Gross unrealized losses | (127)
Fair value | 98,910
Asset-backed securities | Long-Term Investments |
Debt Securities, Available-for-sale [Line Items] |
Amortized cost | 41,342
Gross unrealized gains | 130
Gross unrealized losses | (12)
Fair value | 41,460
Municipal bonds |
Debt Securities, Available-for-sale [Line Items] |
Gross unrealized losses | (9)
Municipal bonds | Short-Term Investments |
Debt Securities, Available-for-sale [Line Items] |
Amortized cost | 4,492
Gross unrealized gains | 0
Gross unrealized losses | (1)
Fair value | 4,491
Municipal bonds | Long-Term Investments |
Debt Securities, Available-for-sale [Line Items] |
Amortized cost | 855
Gross unrealized gains | 0
Gross unrealized losses | (8)
Fair value | 847
Sovereign bonds |
Debt Securities, Available-for-sale [Line Items] |
Gross unrealized losses | (12)
Sovereign bonds | Short-Term Investments |
Debt Securities, Available-for-sale [Line Items] |
Amortized cost | 10,898
Gross unrealized gains | 14
Gross unrealized losses | (12)
Fair value | 10,900
Sovereign bonds | Long-Term Investments |
Debt Securities, Available-for-sale [Line Items] |
Amortized cost | 10,876
Gross unrealized gains | 15
Gross unrealized losses | 0
Fair value | 10,891
Agency bonds |
Debt Securities, Available-for-sale [Line Items] |
Gross unrealized losses | (17)
Agency bonds | Long-Term Investments |
Debt Securities, Available-for-sale [Line Items] |
Amortized cost | 5,930
Gross unrealized gains | 0
Gross unrealized losses | (17)
Fair value | $ 5,913

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- Definition Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563 + Details
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