Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017	Jan. 01, 2017
Income Tax [Line Items]
U.S. federal statutory income tax rate	21.00%		35.00%
Reduction in deferred tax assets due to tax cuts and jobs act			$ 420,000
Deferred tax expenses on repatriation of foreign earnings			$ 1,000
Income tax provisions	$ 24,167	$ 39,767
Effective income tax rates	13.00%	26.50%
Adjustments for New Accounting Principle [Member]
Income Tax [Line Items]
Income tax provisions	$ 26,134	$ 7,356
Deferred tax assets recorded for previously unrecognized excess tax benefits on share-based payment awards				$ 81,544
Deferred tax assets, valuation allowance				$ 12,090