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Investments and Fair Value Measurements - Available-For-Sale Investments (Details) - USD ($) $ in Thousands | Sep. 30, 2022 | Dec. 31, 2021
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | $ 643,216 | $ 892,948
Gross Unrealized Gain | 0 | 1
Gross Unrealized Loss | (12,102) | (2,243)
Fair Value | 631,114 | 890,706
U.S. Treasury securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 333,851 | 425,560
Gross Unrealized Gain | 0 | 1
Gross Unrealized Loss | (5,983) | (1,086)
Fair Value | 327,868 | 424,475
Corporate notes and bonds |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 242,536 | 209,550
Gross Unrealized Gain | 0 | 0
Gross Unrealized Loss | (5,421) | (925)
Fair Value | 237,115 | 208,625
Commercial paper |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 6,498 | 124,098
Gross Unrealized Gain | 0 | 0
Gross Unrealized Loss | 0 | (9)
Fair Value | 6,498 | 124,089
Asset-backed securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 37,938 | 98,857
Gross Unrealized Gain | 0 | 0
Gross Unrealized Loss | (397) | (140)
Fair Value | 37,541 | 98,717
Municipal securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 2,323 | 4,577
Gross Unrealized Gain | 0 | 0
Gross Unrealized Loss | (107) | (15)
Fair Value | 2,216 | 4,562
Foreign government and supranational securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 20,070 | 30,306
Gross Unrealized Gain | 0 | 0
Gross Unrealized Loss | (194) | (68)
Fair Value | $ 19,876 | $ 30,238

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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 https://asc.fasb.org/extlink&oid=126970911&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 https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563 + Details
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