Income Taxes Components of Income Tax Expense (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Current tax provision (benefit)
Federal									$ 4,076	$ 2,365
State									(267)	672
Interest and Penalties									0	119
Total Current Provision for Income taxes, net									3,809	3,156
Deferred Provision (Benefit) for Income Taxes
Federal									85	0
State									(407)	0
Total Deferred Benefit for Income Taxes, net									(322)	0
Income Tax Expense (Benefit)	$ 2,215	$ (1,155)	$ 2,115	$ 312	$ 917	$ 2,239	$ 0	$ 0	$ 3,487	$ 3,156	$ 0