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Investments in Marketable Debt Securities, Available-for-Sale - Schedule of Amortized Cost and Fair Value of Marketable Securities, Available-for-Sale, by Type of Security (Detail) - USD ($) $ in Thousands | Jun. 30, 2022 | Dec. 31, 2021
--- | --- | ---
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | $ 335,254 | $ 295,773
Fair Value | 330,628 | 296,478
Short-term investments [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 254,487 | 183,915
Allowance for Credit Losses | 0 | 0
Gross Unrealized Gains | 1 | 22
Gross Unrealized Losses | (1,448) | (69)
Fair Value | 253,040 | 183,868
Short-term investments [Member] | U.S. Treasuries [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 123,715 | 35,767
Allowance for Credit Losses | 0 | 0
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (1,233) | (34)
Fair Value | 122,482 | 35,733
Short-term investments [Member] | Corporate debt [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 129,913 | 148,148
Allowance for Credit Losses | 0 | 0
Gross Unrealized Gains | 0 | 22
Gross Unrealized Losses | (206) | (35)
Fair Value | 129,707 | 148,135
Short-term investments [Member] | ABS and other [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 859 |
Allowance for Credit Losses | 0 |
Gross Unrealized Gains | 1 |
Gross Unrealized Losses | (9) |
Fair Value | 851 |
Long-term marketable securities [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 80,767 | 111,858
Allowance for Credit Losses | 0 | 0
Gross Unrealized Gains | 4 | 1,194
Gross Unrealized Losses | (3,183) | (442)
Fair Value | 77,588 | 112,610
Long-term marketable securities [Member] | U.S. Treasuries [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 40,827 | 70,902
Allowance for Credit Losses | 0 | 0
Gross Unrealized Gains | 0 | 128
Gross Unrealized Losses | (619) | (263)
Fair Value | 40,208 | 70,767
Long-term marketable securities [Member] | U.S. Government Sponsored Entities [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 646 | 726
Allowance for Credit Losses | 0 | 0
Gross Unrealized Gains | 0 | 22
Gross Unrealized Losses | (42) | (3)
Fair Value | 604 | 745
Long-term marketable securities [Member] | Corporate debt [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 31,956 | 33,197
Allowance for Credit Losses | 0 | 0
Gross Unrealized Gains | 1 | 962
Gross Unrealized Losses | (2,100) | (146)
Fair Value | 29,857 | 34,013
Long-term marketable securities [Member] | ABS and other [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 7,338 | 7,033
Allowance for Credit Losses | 0 | 0
Gross Unrealized Gains | 3 | 82
Gross Unrealized Losses | (422) | (30)
Fair Value | $ 6,919 | $ 7,085

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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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