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Income Taxes - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended								12 Months Ended
	Jan. 01, 2018	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Taxes [Line Items]
Income tax holiday amount										$ 28,000	$ 25,000	$ 23,000
Income tax holiday per share benefit										$ 0.36	$ 0.31	$ 0.29
Effective income tax rate										13.00%	96.80%	13.10%
2017 Tax Act											$ 550,000
2017 Tax Act, Transition tax											490,000
2017 Tax Act, State income taxes and foreign withholding taxes											40,000
2017 Tax Act, Remeasurement of deferred taxes											$ 20,000
Statutory tax rate											21.00%	35.00%
Net income per diluted common share		$ 2.46	$ 1.83	$ 1.98	$ 1.40	$ (4.44)	$ 1.69	$ 1.63	$ 1.31	$ 7.65	$ 0.25	$ 6.41
Effective income tax rate											11.00%
Net additions for tax positions taken during the prior period										$ 17,651
Incremental income tax provision		$ 12,654	$ 28,216	$ 18,884	$ 28,598	$ 578,910	$ 17,696	$ 16,250	$ 7,930	88,352	$ 620,786	$ 78,611
Effect of stock-based compensation										9,089	19,566
Release of valuation allowance												$ (3,000)
Percentage point in effective tax rate related to valuation allowance on certain net operating loss carryforwards												(0.7)
Valuation allowances		53,893				62,098				53,893	62,098
Deferred tax assets, net of valuation allowance		81,886				$ 79,165				81,886	$ 79,165
Tax benefit related to stock option plan												$ 13,844
Accounting Standards Update 2016-16 [Member]
Income Taxes [Line Items]
Retained earnings	$ 4,000
Foreign net operating losses and credits [Member]
Income Taxes [Line Items]
Gross foreign net operating losses		240,000								240,000
Valuation allowances		51,000								51,000
Deferred tax assets, net of valuation allowance		12,000								$ 12,000
Change in statutory tax rate [Member]
Income Taxes [Line Items]
2017 Tax Act, change in foreign currency exchange rates on earnings, percentage										(0.02)
GILTI tax [Member]
Income Taxes [Line Items]
2017 Tax Act, change in foreign currency exchange rates on earnings, percentage										0.020
Change in Indefinite Reinvestment Assertion for Investments in Foreign Subsidiaries [Member]
Income Taxes [Line Items]
2017 Tax Act, change in foreign currency exchange rates on earnings, percentage										0.006
Stock Based Compensation Tax Benefit [Member]
Income Taxes [Line Items]
Net income per diluted common share										$ 0.11	$ 0.24
2017 Tax Act [Member]
Income Taxes [Line Items]
Net income per diluted common share											$ (6.82)
Reduction in provisional accrual for federal, state and foreign taxes										$ (24,000)
Net additions for tax positions taken during the prior period										17,651
Incremental income tax provision										(6,000)
2017 Tax Act [Member] | Foreign Currency Translation Adjustment [Member]
Income Taxes [Line Items]
Incremental income tax provision										7,000
Maximum [Member]
Income Taxes [Line Items]
Expected change in unrecognized tax benefits in the next twelve months		$ (1,000)								$ (1,000)
United States [Member]
Income Taxes [Line Items]
Statutory tax rate										21.00%
Ireland [Member]
Income Taxes [Line Items]
Statutory tax rate										12.50%
U.K [Member]
Income Taxes [Line Items]
Statutory tax rate										19.00%
Singapore [Member]
Income Taxes [Line Items]
Statutory tax rate										17.00%
Singapore [Member] | Contractual Tax Rate Singapore [Member]
Income Taxes [Line Items]
Marginal effective income tax rate										0.00%

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