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Financial Instruments - Summary of Investments (Detail) - USD ($) $ in Thousands | Mar. 31, 2022 | Dec. 31, 2021
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Short-term, Municipal Bonds [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Total short-term investments (available for sale), Cost | $ 5,000 | $ 5,028
Total short-term investments (available for sale), Gross Unrealized (Loss) |  | (1)
Total short-term investments (available for sale), Fair value | 5,000 | 5,027
Short-term, Non-governmental Debt Securities [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Total short-term investments (available for sale), Cost | 208,401 | 168,623
Total short-term investments (available for sale), Gross Unrealized Gain | 3 | 27
Total short-term investments (available for sale), Gross Unrealized (Loss) | (1,192) | (184)
Total short-term investments (available for sale), Fair value | 207,212 | 168,466
Short-term, Treasury and Federal Agencies [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Total short-term investments (available for sale), Cost | 95,737 | 720
Total short-term investments (available for sale), Gross Unrealized (Loss) | (329) |
Total short-term investments (available for sale), Fair value | 95,408 | 720
Short-term Investments [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Total short-term investments (available for sale), Cost | 309,138 | 174,371
Total short-term investments (available for sale), Gross Unrealized Gain | 3 | 27
Total short-term investments (available for sale), Gross Unrealized (Loss) | (1,521) | (185)
Total short-term investments (available for sale), Fair value | $ 307,620 | $ 174,213

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