Fair Value Measurements - Summary of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Recurring
Liabilities
Contingent consideration	$ (6,198)	$ (10,612)
Temporary Equity
Redeemable noncontrolling interest		(151,978)
Recurring \| Level 1
Liabilities
Contingent consideration	0	0
Temporary Equity
Redeemable noncontrolling interest		0
Recurring \| Level 2
Liabilities
Contingent consideration	0	0
Temporary Equity
Redeemable noncontrolling interest		0
Recurring \| Level 3
Liabilities
Contingent consideration	(6,198)	(10,612)
Temporary Equity
Redeemable noncontrolling interest		(151,978)
Foreign currency exchange contracts \| Recurring
Assets
Foreign currency exchange contracts		1,912
Liabilities
Foreign currency exchange contracts	(237)	(1,110)
Foreign currency exchange contracts \| Recurring \| Level 1
Assets
Foreign currency exchange contracts		0
Liabilities
Foreign currency exchange contracts	0	0
Foreign currency exchange contracts \| Recurring \| Level 2
Assets
Foreign currency exchange contracts		1,912
Liabilities
Foreign currency exchange contracts	(237)	(1,110)
Foreign currency exchange contracts \| Recurring \| Level 3
Assets
Foreign currency exchange contracts		0
Liabilities
Foreign currency exchange contracts	0	0
Interest rate cap contracts
Assets
Interest rate cap contracts	2,023	0
Interest rate cap contracts \| Recurring
Assets
Interest rate cap contracts	2,023	3,922
Interest rate cap contracts \| Recurring \| Level 1
Assets
Interest rate cap contracts	0	0
Interest rate cap contracts \| Recurring \| Level 2
Assets
Interest rate cap contracts	2,023	3,922
Interest rate cap contracts \| Recurring \| Level 3
Assets
Interest rate cap contracts	0	0
Interest rate swap agreements \| Recurring
Liabilities
Interest rate swap agreements	(4,881)	(7)
Interest rate swap agreements \| Recurring \| Level 1
Liabilities
Interest rate swap agreements	0	0
Interest rate swap agreements \| Recurring \| Level 2
Liabilities
Interest rate swap agreements	(4,881)	(7)
Interest rate swap agreements \| Recurring \| Level 3
Liabilities
Interest rate swap agreements	$ 0	$ 0

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Amount of liability recognized arising from contingent consideration in a business combination.

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Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets.

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