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Cash, Cash Equivalents, and Investments - Summary of Available-for-Sale Investments (Detail) $ in Thousands | Jun. 30, 2019 USD ($)
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Debt Securities, Available-for-sale [Line Items] |
Amortized cost | $ 769,801
Gross unrealized gains | 2,985
Gross unrealized losses | (267)
Fair value | 772,519
Agency Bonds |
Debt Securities, Available-for-sale [Line Items] |
Gross unrealized losses | (27)
Agency Bonds | Short-Term Investments |
Debt Securities, Available-for-sale [Line Items] |
Amortized cost | 7,780
Gross unrealized gains | 3
Gross unrealized losses | 0
Fair value | 7,783
Agency Bonds | Long-Term Investments |
Debt Securities, Available-for-sale [Line Items] |
Amortized cost | 5,930
Gross unrealized gains | 0
Gross unrealized losses | (27)
Fair value | 5,903
Treasury Bills |
Debt Securities, Available-for-sale [Line Items] |
Gross unrealized losses | (20)
Treasury Bills | Short-Term Investments |
Debt Securities, Available-for-sale [Line Items] |
Amortized cost | 138,217
Gross unrealized gains | 383
Gross unrealized losses | 0
Fair value | 138,600
Treasury Bills | Long-Term Investments |
Debt Securities, Available-for-sale [Line Items] |
Amortized cost | 167,653
Gross unrealized gains | 1,257
Gross unrealized losses | (20)
Fair value | 168,890
Corporate Bonds |
Debt Securities, Available-for-sale [Line Items] |
Gross unrealized losses | (176)
Corporate Bonds | Short-Term Investments |
Debt Securities, Available-for-sale [Line Items] |
Amortized cost | 101,722
Gross unrealized gains | 182
Gross unrealized losses | (36)
Fair value | 101,868
Corporate Bonds | Long-Term Investments |
Debt Securities, Available-for-sale [Line Items] |
Amortized cost | 176,726
Gross unrealized gains | 537
Gross unrealized losses | (140)
Fair value | 177,123
Asset-Backed Securities |
Debt Securities, Available-for-sale [Line Items] |
Gross unrealized losses | (37)
Asset-Backed Securities | Short-Term Investments |
Debt Securities, Available-for-sale [Line Items] |
Amortized cost | 104,717
Gross unrealized gains | 317
Gross unrealized losses | (36)
Fair value | 104,998
Asset-Backed Securities | Long-Term Investments |
Debt Securities, Available-for-sale [Line Items] |
Amortized cost | 40,198
Gross unrealized gains | 237
Gross unrealized losses | (1)
Fair value | 40,434
Sovereign Bonds |
Debt Securities, Available-for-sale [Line Items] |
Gross unrealized losses | (1)
Sovereign Bonds | Short-Term Investments |
Debt Securities, Available-for-sale [Line Items] |
Amortized cost | 5,979
Gross unrealized gains | 12
Gross unrealized losses | (1)
Fair value | 5,990
Sovereign Bonds | Long-Term Investments |
Debt Securities, Available-for-sale [Line Items] |
Amortized cost | 14,783
Gross unrealized gains | 50
Gross unrealized losses | 0
Fair value | 14,833
Municipal Bonds |
Debt Securities, Available-for-sale [Line Items] |
Gross unrealized losses | (6)
Municipal Bonds | Short-Term Investments |
Debt Securities, Available-for-sale [Line Items] |
Amortized cost | 5,241
Gross unrealized gains | 7
Gross unrealized losses | 0
Fair value | 5,248
Municipal Bonds | Long-Term Investments |
Debt Securities, Available-for-sale [Line Items] |
Amortized cost | 855
Gross unrealized gains | 0
Gross unrealized losses | (6)
Fair value | $ 849

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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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