Income Taxes - Narrative (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Income Tax Disclosure [Abstract]
Unrecognized tax benefits	$ 1,300,000	$ 196,000	$ 1,300,000	$ 196,000
Interest and penalties	$ 3,600	$ 0	$ 22,000	$ 0
Effective income tax rate (as percent)	31.70%	33.90%	29.00%	33.50%
Federal and State income tax statutory rate (as percent)			39.23%
Excess tax benefit	$ 789,000		$ 4,600,000