Income Taxes - Income Tax Provision (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Current income tax expense
Federal									$ 3,158	$ 4,572	$ 381
State									1,283	2,423	358
Total current income tax expense									4,441	6,995	739
Deferred income tax expense (benefit)
Federal									69	(458)	0
State									25	(142)	0
Total deferred income tax expense (benefit)									94	(600)	0
Total provision	$ 64	$ 3,048	$ 1,178	$ 245	$ 1,727	$ 1,100	$ 538	$ 3,030	$ 4,535	$ 6,395	$ 739