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Fair Value Measurements - Schedule of Fair Value Liabilities Measured On Recurring Basis Valuation Techniques (Detail) - Contingent Consideration [Member] $ in Thousands | Dec. 31, 2019 USD ($) yr | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($)
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Fair Value, Amount | $ | $ 4,788 | $ 2,875 | $ 0
Level 3 [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Fair Value, Amount | $ | $ 4,788 | $ 2,875 |
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 | 5.8 |  |
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 | 0.4 |  |
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 | 2.3 |  |
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 | 0.050 |  |
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 | 0.036 |  |
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 | 0.041 |  |
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 | 1.000 |  |
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 | 0.330 |  |
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 | 0.818 |  |
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 | $ | $ 4,788 |  |

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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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