Accumulated Other Comprehensive Income (Changes in AOCI) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			$ 1,007
Other comprehensive income, net of tax	$ 282	$ 203	1,238	$ 2,410	$ 482
Ending balance	2,245	2,935	2,245	2,935	1,007
Gains and Losses on Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			(679)	(935)	(935)
Other comprehensive gain before reclassifications			180	53
Amounts reclassified from accumulated other comprehensive income			0	0
Other comprehensive income, net of tax			180	53
Ending balance	(499)	(882)	(499)	(882)	(679)
Unrealized Gains and Losses on Available-for-Sale Securities
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			1,686	1,460	1,460
Other comprehensive gain before reclassifications			1,263	2,580
Amounts reclassified from accumulated other comprehensive income			(205)	(223)
Other comprehensive income, net of tax			1,058	2,357
Ending balance	$ 2,744	$ 3,817	$ 2,744	$ 3,817	$ 1,686