Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Reserves for uncertain tax positions net	$ 166,279,000	$ 115,787,000
Reduction in the provision for income taxes, if reserves not realized	166,000,000
Interest and penalties resulted in an income tax expense	$ 3,000,000	1,000,000	$ 7,000,000
Operational period	12 months
Federal statutory income tax rate	20.25%
Foreign tax credits	$ 15,000,000	17,000,000	$ 15,000,000
Undistributed earnings of subsidiaries	$ 0	$ 0