Income Taxes - Provision For Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current tax expense
Federal		$ 62,216	$ 50,794	$ 67,985
State		8,163	5,476	6,278
Foreign		745	592	1,689
Deferred tax (benefit) expense
Federal		(7,723)	(112)	(21,398)
State		(2,655)	(737)	(2,116)
Foreign		(137)	(57)	(153)
Income taxes	$ 9,215	$ 60,609	$ 55,956	$ 52,285