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Fair Value Measurements - Schedule of Assets and Liabilities at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands | Jun. 30, 2022 | Dec. 31, 2021 | Jun. 30, 2021 | Dec. 31, 2020
--- | --- | --- | --- | ---
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Assets held in rabbi trust | $ 9,587 | $ 11,508 |  |
Marketable debt securities, available-for-sale | 330,628 | 296,478 |  |
Deferred consideration | 6,163 | 9,801 |  |
Deferred compensation liability | 7,039 | 8,001 |  |
Short-term investments [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 253,040 | 183,868 |  |
Long-term marketable securities [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 77,588 | 112,610 |  |
U.S. Treasuries [Member] | Short-term investments [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 122,482 | 35,733 |  |
U.S. Treasuries [Member] | Long-term marketable securities [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 40,208 | 70,767 |  |
U.S. Government Sponsored Entities [Member] | Long-term marketable securities [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 604 | 745 |  |
Corporate debt securities [Member] | Short-term investments [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 129,707 | 148,135 |  |
Corporate debt securities [Member] | Long-term marketable securities [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 29,857 | 34,013 |  |
Asset-backed securities and other [Member] | Short-term investments [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 851 |  |  |
Asset-backed securities and other [Member] | Long-term marketable securities [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 6,919 | 7,085 |  |
Recurring [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Cash and cash equivalents | 116,842 | 219,933 |  |
Recurring [Member] | Short-term investments [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 253,040 | 183,868 |  |
Recurring [Member] | Long-term marketable securities [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 77,588 | 112,610 |  |
Recurring [Member] | Commercial Paper [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Cash and cash equivalents | 35,932 | 8,948 |  |
Recurring [Member] | Money market funds [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Cash and cash equivalents | 80,910 | 210,985 |  |
Recurring [Member] | Assets held in rabbi trust [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Assets held in rabbi trust | 9,587 | 11,508 |  |
Recurring [Member] | U.S. Treasuries [Member] | Short-term investments [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 122,482 | 35,733 |  |
Recurring [Member] | U.S. Treasuries [Member] | Long-term marketable securities [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 40,208 | 70,767 |  |
Recurring [Member] | U.S. Government Sponsored Entities [Member] | Long-term marketable securities [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 604 | 745 |  |
Recurring [Member] | Corporate debt securities [Member] | Short-term investments [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 129,707 | 0 |  |
Recurring [Member] | Corporate debt securities [Member] | Long-term marketable securities [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 29,857 | 34,013 |  |
Recurring [Member] | Asset-backed securities and other [Member] | Short-term investments [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 851 | 148,135 |  |
Recurring [Member] | Asset-backed securities and other [Member] | Long-term marketable securities [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 6,919 | 7,085 |  |
Level 1 [Member] | Recurring [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Cash and cash equivalents | 80,910 | 210,985 |  |
Deferred consideration | 0 | 0 |  |
Deferred compensation liability | 7,039 | 8,001 |  |
Level 1 [Member] | Recurring [Member] | Short-term investments [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 122,482 | 35,733 |  |
Level 1 [Member] | Recurring [Member] | Long-term marketable securities [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 40,208 | 70,767 |  |
Level 1 [Member] | Recurring [Member] | Commercial Paper [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Cash and cash equivalents | 0 | 0 |  |
Level 1 [Member] | Recurring [Member] | Money market funds [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Cash and cash equivalents | 80,910 | 210,985 |  |
Level 1 [Member] | Recurring [Member] | Assets held in rabbi trust [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Assets held in rabbi trust | 0 | 0 |  |
Level 1 [Member] | Recurring [Member] | U.S. Treasuries [Member] | Short-term investments [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 122,482 | 35,733 |  |
Level 1 [Member] | Recurring [Member] | U.S. Treasuries [Member] | Long-term marketable securities [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 40,208 | 70,767 |  |
Level 1 [Member] | Recurring [Member] | U.S. Government Sponsored Entities [Member] | Long-term marketable securities [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 0 | 0 |  |
Level 1 [Member] | Recurring [Member] | Corporate debt securities [Member] | Short-term investments [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 0 | 0 |  |
Level 1 [Member] | Recurring [Member] | Corporate debt securities [Member] | Long-term marketable securities [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 0 | 0 |  |
Level 1 [Member] | Recurring [Member] | Asset-backed securities and other [Member] | Short-term investments [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 0 | 0 |  |
Level 1 [Member] | Recurring [Member] | Asset-backed securities and other [Member] | Long-term marketable securities [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 0 | 0 |  |
Level 2 [Member] | Recurring [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Cash and cash equivalents | 35,932 | 8,948 |  |
Deferred consideration | 6,163 | 9,801 |  |
Deferred compensation liability | 0 | 0 |  |
Level 2 [Member] | Recurring [Member] | Short-term investments [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 130,558 | 148,135 |  |
Level 2 [Member] | Recurring [Member] | Long-term marketable securities [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 37,380 | 41,843 |  |
Level 2 [Member] | Recurring [Member] | Commercial Paper [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Cash and cash equivalents | 35,932 | 8,948 |  |
Level 2 [Member] | Recurring [Member] | Money market funds [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Cash and cash equivalents | 0 | 0 |  |
Level 2 [Member] | Recurring [Member] | Assets held in rabbi trust [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Assets held in rabbi trust | 9,587 | 11,508 |  |
Level 2 [Member] | Recurring [Member] | U.S. Treasuries [Member] | Short-term investments [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 0 | 0 |  |
Level 2 [Member] | Recurring [Member] | U.S. Treasuries [Member] | Long-term marketable securities [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 0 | 0 |  |
Level 2 [Member] | Recurring [Member] | U.S. Government Sponsored Entities [Member] | Long-term marketable securities [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 604 | 745 |  |
Level 2 [Member] | Recurring [Member] | Corporate debt securities [Member] | Short-term investments [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 129,707 | 0 |  |
Level 2 [Member] | Recurring [Member] | Corporate debt securities [Member] | Long-term marketable securities [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 29,857 | 34,013 |  |
Level 2 [Member] | Recurring [Member] | Asset-backed securities and other [Member] | Short-term investments [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 851 | 148,135 |  |
Level 2 [Member] | Recurring [Member] | Asset-backed securities and other [Member] | Long-term marketable securities [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 6,919 | 7,085 |  |
Level 3 [Member] | Recurring [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Cash and cash equivalents | 0 | 0 |  |
Deferred consideration | 0 | 0 |  |
Deferred compensation liability | 0 | 0 |  |
Level 3 [Member] | Recurring [Member] | Short-term investments [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 0 | 0 |  |
Level 3 [Member] | Recurring [Member] | Long-term marketable securities [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 0 | 0 |  |
Level 3 [Member] | Recurring [Member] | Commercial Paper [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Cash and cash equivalents | 0 | 0 |  |
Level 3 [Member] | Recurring [Member] | Money market funds [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Cash and cash equivalents | 0 | 0 |  |
Level 3 [Member] | Recurring [Member] | Assets held in rabbi trust [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Assets held in rabbi trust | 0 | 0 |  |
Level 3 [Member] | Recurring [Member] | U.S. Treasuries [Member] | Short-term investments [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 0 | 0 |  |
Level 3 [Member] | Recurring [Member] | U.S. Treasuries [Member] | Long-term marketable securities [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 0 | 0 |  |
Level 3 [Member] | Recurring [Member] | U.S. Government Sponsored Entities [Member] | Long-term marketable securities [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 0 | 0 |  |
Level 3 [Member] | Recurring [Member] | Corporate debt securities [Member] | Short-term investments [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 0 | 0 |  |
Level 3 [Member] | Recurring [Member] | Corporate debt securities [Member] | Long-term marketable securities [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 0 | 0 |  |
Level 3 [Member] | Recurring [Member] | Asset-backed securities and other [Member] | Short-term investments [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 0 | 0 |  |
Level 3 [Member] | Recurring [Member] | Asset-backed securities and other [Member] | Long-term marketable securities [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Marketable debt securities, available-for-sale | 0 | 0 |  |
Contingent Consideration [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Contingent consideration | 7,779 | 9,312 | $ 6,817 | $ 5,572
Contingent Consideration [Member] | Level 1 [Member] | Recurring [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Contingent consideration | 0 | 0 |  |
Contingent Consideration [Member] | Level 2 [Member] | Recurring [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Contingent consideration | 0 | 0 |  |
Contingent Consideration [Member] | Level 3 [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Contingent consideration | $ 7,779 | $ 9,312 |  |

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