Other Comprehensive Income (Loss) (Activity in Other Comprehensive Income) (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2020	Mar. 31, 2019
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent [Abstract]
Changes in fair value of available for sale debt securities, before tax		$ 16,740	$ 14,406
Changes in fair value of available for sale debt securities, tax		3,934	3,385
Changes in fair value of available for sale debt securities		12,806	11,021
Net gains (losses) on debt securities reclassified into earnings, before tax		0	0
Net gains (losses) on debt securities reclassified into earnings, tax		0	0
Net gains (losses) on debt securities reclassified into earnings		0	0
Net change in fair value of available for sale debt securities, before tax		16,740	14,406
Net change in fair value of available for sale debt securities, tax		3,934	3,385
Net change in fair value of available for sale debt securities		12,806	11,021
Change in fair value of cash flow hedges, before tax		(1,402)	(546)
Change in fair value of cash flow hedges, tax		(330)	(128)
Change in fair value of cash flow hedges		(1,072)	(418)
Net cash flow hedge losses reclassified into earnings, before tax	[1]	29	(31)
Net cash flow hedge losses reclassified into earnings, tax	[1]	7	(7)
Net cash flow hedge losses reclassified into earnings	[1]	22	(24)
Net change in fair value of cash flow hedges, before tax		(1,373)	(577)
Net change in fair value of cash flow hedges, tax		(323)	(135)
Net change in fair value of cash flow hedges		(1,050)	(442)
Amortization of net actuarial losses, before tax	[2]	536	300
Amortization of net actuarial losses, tax	[2]	126	70
Amortization of net actuarial losses	[2]	410	230
Amortization of net prior service credits, before tax	[2]	0	(4)
Amortization of net prior service credits, tax	[2]	0	(1)
Amortization of net prior service credits	[2]	0	(3)
Net change in defined benefit plan obligations, before tax		536	296
Net change in defined benefit plan obligations, tax		126	69
Net change in defined benefit plan obligations		410	227
Total other comprehensive income (loss), before tax		15,903	14,125
Total other comprehensive income (loss), tax		3,737	3,319
Total other comprehensive income (loss), net of tax		$ 12,166	$ 10,806

[1] The pre-tax amounts are included in interest expense on FHLB advances, interest expense on junior subordinated debentures and interest and fees on loans in the Unaudited Consolidated Statements of Income.

[2] The pre-tax amounts are included in other expenses in the Unaudited Consolidated Statements of Income.