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Fair Value of Financial Assets and Liabilities - Changes in Level 3 Liabilities Measured at Fair Value on Recurring Basis (Detail) - Level 3 [Member] - Accounts Payable Accrued and Other Liabilities [Member] - Contingent Consideration [Member] - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] |  |
Opening Balance, Liabilities | $ 42,159 | $ 45,984
Total realized and unrealized (gains) losses included in Net income (loss), Liabilities | 4,661 | 5,622
Unrealized (gains) losses included in Other comprehensive income (loss), Liabilities | 55 | (3)
Purchases/ Issuances, Liabilities | 2,959 |
Sales/ Settlements, Liabilities | (10,043) | (9,444)
Closing Balance, Liabilities | 39,791 | 42,159
Unrealized (gains) losses for the period included in Net income (loss) on Level 3 Assets/Liabilities Outstanding | $ 4,649 |
Unrealized (gains) losses for the period on Level 3 Assets/Liabilities Outstanding |  | $ 5,622

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- Definition Fair value measurement with unobservable inputs reconciliation recurring basis liability net, unrealized gain (loss). + References No definition available. + Details
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- Definition Fair value measurement with unobservable inputs reconciliation recurring basis liability net unrealized gain loss included in net income (loss). + References No definition available. + Details
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- Definition Fair value measurement with unobservable inputs reconciliation recurring basis liability purchases and issuances. + References No definition available. + Details
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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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- Definition Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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- Definition Amount of gain (loss) recognized in other comprehensive income (OCI) from liability measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1a) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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