Accumulated Other Comprehensive Loss ("AOCL"), Reclassification Out of Each components (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total reclassifications before tax	$ 8,594	$ 9,049	$ 17,189	$ 15,106
Income tax expense	2,663	2,611	5,284	4,568
Reclassifications, net of tax	5,931	6,438	11,905	10,538
Unrealized Gains 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	11	109	117	283
Net impairment loss recognized in earnings	0	0	0	0
Total reclassifications before tax	11	109	117	283
Income tax expense	4	37	41	99
Reclassifications, net of tax	$ 7	$ 72	$ 76	$ 184