Income Taxes - Components of Income Tax Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Federal
Current	$ 101,821	$ 85,330	$ 95,046
Deferred	(42,474)	16,903	17,631
Federal income tax expense, total	59,347	102,233	112,677
State
Current	20,490	16,082	16,973
Deferred	(1,221)	(1,068)	368
State and local income tax expense, total	19,269	15,014	17,341
Foreign
Current	149,596	137,076	147,174
Deferred	0	0	0
Foreign income tax expense, total	149,596	137,076	147,174
Total
Current	271,907	238,488	259,193
Deferred	(43,695)	15,835	17,999
Income tax expense	$ 228,212	$ 254,323	$ 277,192