Fair Value of Financial Instruments (Servicing Assets) (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2017	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Default rate assumption, default rate increase of 25%	25.00%
Default rate assumption, default rate increase of 50%	50.00%
Cost to service assumption, cost to service increase by 25%	25.00%
Cost to service assumption, cost to service increase by 50%	50.00%
Default rate increase	$ (62)	$ (98)
Default rate increase	(120)	(188)
Cost to service increase	(48)	(60)
Cost to service increase	$ (95)	$ (120)