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Fair Value Measurements - Schedule of Fair Value Liabilities Measured On Recurring Basis Valuation Techniques (Detail) - Contingent Consideration [Member] $ in Thousands | Jun. 30, 2021 USD ($) yr | Dec. 31, 2020 USD ($) yr | Jun. 30, 2020 USD ($) | Dec. 31, 2019 USD ($)
--- | --- | --- | --- | ---
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Fair Value, Amount | $ | $ 6,817 | $ 5,572 | $ 5,208 | $ 3,387
Level 3 [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Fair Value, Amount | $ | $ 6,817 | $ 5,572 |  |
Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | Expected life of cash flows [Member] | Maximum [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Fair Value, Range | yr | 6.3 | 6.8 |  |
Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | Expected life of cash flows [Member] | Minimum [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Fair Value, Range | yr | 1.9 | 2.4 |  |
Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | Expected life of cash flows [Member] | Weighted Average [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Fair Value, Range | yr | 3.8 | 4.4 |  |
Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | Discount rate [Member] | Maximum [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Fair Value, Range | 3.7 | 4.3 |  |
Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | Discount rate [Member] | Minimum [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Fair Value, Range | 1.9 | 2.6 |  |
Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | Discount rate [Member] | Weighted Average [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Fair Value, Range | 2.8 | 3.4 |  |
Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | Probability of achievement [Member] | Maximum [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Fair Value, Range | 100.0 | 100.0 |  |
Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | Probability of achievement [Member] | Minimum [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Fair Value, Range | 33.8 | 50.0 |  |
Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | Probability of achievement [Member] | Weighted Average [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Fair Value, Range | 90.1 | 86.1 |  |
Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | Discounted cash flow [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Fair Value, Amount | $ | $ 6,817 | $ 5,572 |  |

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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