Acquisitions and Divestiture - Pro Forma Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Business Acquisition, Pro Forma Information [Abstract]
Total revenues actual since acquisition	$ 111,168
Net income (loss) actual since acquisition	(21,175)
Total revenues pro forma	5,132,662	$ 5,406,291
Net income (loss) pro forma	$ 1,011,463	$ 1,445,779