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Fair Value Measurements - Schedule of Reconciliation of Contingent Consideration Measured at Fair Value on Recurring Basis (Detail) - Contingent Consideration [Member] - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Beginning balance | $ 2,875 | $ 0
Contingent consideration in connection with acquisitions | 2,382 | 2,674
Change in fair value of contingent consideration | 202 | 201
Payments of contingent consideration | (671) | 0
Ending balance | $ 4,788 | $ 2,875

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- Definition Amount of issuances of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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