Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Current:
Federal	$ 320,726	$ 137,993	$ 120,030
State	33,978	19,051	20,099
Foreign	806	1,252	2,164
Total current	355,510	158,296	142,293
Deferred
Federal	(2,846)	(2,945)	(37,713)
State	7,279	463	(9,059)
Foreign	194	(225)	(1,055)
Total deferred	4,627	(2,707)	(47,827)
Other non-current
Federal	29,678	27,115	7,797
State	2,990	2,383	1,907
Foreign	(7)	19	173
Total other	32,661	29,517	9,877
Total income tax expense	$ 392,798	$ 185,106	$ 104,343