Income Taxes - Summary of Provision for Income Taxes and U.S. Federal Tax Rate (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended	9 Months Ended
	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Sep. 30, 2015	Jun. 30, 2016	Sep. 30, 2016	Sep. 30, 2015
Income Tax Disclosure [Abstract]
Computed “expected” tax expense	$ 59,571			$ 57,875
Foreign income tax differential	(4,265)			(5,860)
Excess tax benefits related to stock-based compensation	(8,247)			0
State taxes net of federal benefits	1,678			2,501
Foreign-sourced nontaxable income	(6,691)			(2,344)
Domestic production activities deduction	(4,282)			(7,950)
Other	2,822			4,365
Provision for income taxes	$ 40,586	$ 46,095	$ 45,822	$ 48,587	$ 91,917	$ 132,503	$ 140,695
Computed “expected” tax expense	35.00%			35.00%
Foreign income tax differential	(2.50%)			(3.50%)
Excess tax benefits related to stock-based compensation	(4.90%)			0.00%
State taxes net of federal benefits	1.00%			1.50%
Foreign-sourced nontaxable income	(3.90%)			(1.40%)
Domestic production activities deduction	(2.50%)			(4.80%)
Other	1.70%			2.60%
Provision for income taxes	23.90%			29.40%