Income Taxes - Components (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Components of income tax expense (benefit)
Income Tax Expense (Benefit)	$ 5,895,000	$ (4,831,000)	$ 16,822,000	$ (1,757,000)
Effective tax rate (as a percent)	34.10%	35.00%	34.80%	33.30%
Deferred Tax Assets, Net	$ 13,984,000		$ 13,984,000		$ 11,266,000
Valuation allowance	$ 0		$ 0