Accumulated Other Comprehensive Loss ("AOCL") (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period			$ 251,092	$ 250,371
Other comprehensive income before reclassifications	$ 278	$ 894	3,215	1,189
Amounts reclassified from AOCL	(10)	0	(194)	(49)
Net current period other comprehensive income	268	894	3,021	1,140
Balance at end of period	250,902	252,980	250,902	252,980
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total reclassifications before tax	9,352	7,325	24,458	21,129
Income tax expense	2,979	2,278	7,547	6,682
Reclassifications, net of tax	6,373	5,047	16,911	14,447
Accumulated Other Comprehensive Loss [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(3,283)	(5,390)	(6,036)	(5,636)
Balance at end of period	(3,015)	(4,496)	(3,015)	(4,496)
Unrealized Gains (Losses) on Securities Available For Sale [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	2,515	408	(238)	162
Other comprehensive income before reclassifications	278	894	3,215	1,189
Amounts reclassified from AOCL	(10)	0	(194)	(49)
Net current period other comprehensive income	268	894	3,021	1,140
Balance at end of period	2,783	1,302	2,783	1,302
Unrealized Gains (Losses) on Securities Available For Sale [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net gains on securities	15	0	298	75
Net impairment loss recognized in earnings	0	0	0	0
Total reclassifications before tax	15	0	298	75
Income tax expense	5	0	104	26
Reclassifications, net of tax	10	0	194	49
Disproportionate Tax Effects from Securities Available for Sale [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(5,798)	(5,798)	(5,798)	(5,798)
Other comprehensive income before reclassifications	0	0	0	0
Amounts reclassified from AOCL	0	0	0	0
Net current period other comprehensive income	0	0	0	0
Balance at end of period	$ (5,798)	$ (5,798)	$ (5,798)	$ (5,798)