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Fair Value Measurements and Available for Sale Investments - Schedule of Available for sale Investments by Security Type (Details) $ in Thousands | Sep. 30, 2019 USD ($)
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Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |
Available-for-sale Investments, Amortized Cost | $ 315,309
Available-for-sale Investments, Gross Unrealized Gains | 464
Available-for-sale Investments, Gross Unrealized Losses | (9)
Available-for-sale Investments, Total Fair Value | 315,764
U S Treasury and Agency Securities |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |
Available-for-sale Investments, Amortized Cost | 185,844
Available-for-sale Investments, Gross Unrealized Gains | 145
Available-for-sale Investments, Gross Unrealized Losses | (4)
Available-for-sale Investments, Total Fair Value | 185,985
Commercial Paper |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |
Available-for-sale Investments, Amortized Cost | 29,887
Available-for-sale Investments, Total Fair Value | 29,887
Corporate Debt Securities |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |
Available-for-sale Investments, Amortized Cost | 99,578
Available-for-sale Investments, Gross Unrealized Gains | 319
Available-for-sale Investments, Gross Unrealized Losses | (5)
Available-for-sale Investments, Total Fair Value | $ 99,892

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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=118939692&loc=d3e27161-111563 + Details
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- Definition Amount, before tax, of unrealized loss 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 (c) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563 + Details
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- Definition Amortized cost of 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://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=118942338&loc=SL82898722-210454 + Details
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