Employee Benefit Plans, Directors' Deferred Compensation Plan (Details) - Directors [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Deferred compensation liability	$ 921		$ 921		$ 940
Deferred interest expense	$ 5	$ 3	$ 14	$ 11