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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
	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

X

- Definition

Fair value measurement with unobservable inputs reconciliation recurring basis liability net, unrealized gain (loss).

+ References

No definition available.

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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.

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- Definition

Fair value measurement with unobservable inputs reconciliation recurring basis liability purchases and issuances.

+ References

No definition available.

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- Definition

Fair value measurement with unobservable inputs reconciliation recurring basis liability sales and settlements.

+ References

No definition available.

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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.

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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

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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

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- Definition

Fair value 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
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-Topic 820
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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