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, 2019	Dec. 31, 2018
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Opening Balance, Liabilities	$ 45,984	$ 41,385
Total realized and unrealized (gains) losses included in Net income (loss), Liabilities	5,622	(1,586)
Unrealized (gains)losses included in Other Comprehensive Income (loss), Liabilities	(3)	1,401
Purchases/ Issuances, Liabilities		17,995
Sales/ Settlements, Liabilities	(9,444)	(13,581)
Closing Balance, Liabilities	42,159	45,984
Unrealized (gains)losses for Level 3 Liabilities Outstanding	$ 5,622	$ (776)

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, 2019

Dec. 31, 2018

Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]

Opening Balance, Liabilities

$ 45,984

$ 41,385

Total realized and unrealized (gains) losses included in Net income (loss), Liabilities

5,622

(1,586)

Unrealized (gains)losses included in Other Comprehensive Income (loss), Liabilities

(3)