Other Comprehensive Income (Loss) (Activity in Other Comprehensive Income) (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 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		$ (2,364)	$ 7,807	$ 14,376	$ 22,213
Changes in fair value of available for sale debt securities, tax		(556)	1,835	3,378	5,220
Changes in fair value of available for sale debt securities		(1,808)	5,972	10,998	16,993
Net gains (losses) on debt securities reclassified into earnings, before tax	[1]	0	80	0	80
Net gains (losses) on debt securities reclassified into earnings, tax	[1]	0	19	0	19
Net gains (losses) on debt securities reclassified into earnings	[1]	0	61	0	61
Net change in fair value of available for sale debt securities, before tax		(2,364)	7,887	14,376	22,293
Net change in fair value of available for sale debt securities, tax		(556)	1,854	3,378	5,239
Net change in fair value of available for sale debt securities		(1,808)	6,033	10,998	17,054
Change in fair value of cash flow hedges, before tax		(293)	(824)	(1,848)	(1,370)
Change in fair value of cash flow hedges, tax		(69)	(194)	(434)	(322)
Change in fair value of cash flow hedges		(224)	(630)	(1,414)	(1,048)
Net cash flow hedge losses reclassified into earnings, before tax	[2]	305	10	485	(21)
Net cash flow hedge losses reclassified into earnings, tax	[2]	73	2	113	(5)
Net cash flow hedge losses reclassified into earnings	[2]	232	8	372	(16)
Net change in fair value of cash flow hedges, before tax		12	(814)	(1,363)	(1,391)
Net change in fair value of cash flow hedges, tax		4	(192)	(321)	(327)
Net change in fair value of cash flow hedges		8	(622)	(1,042)	(1,064)
Amortization of net actuarial losses, before tax	[3]	535	300	1,071	600
Amortization of net actuarial losses, tax	[3]	126	71	252	141
Amortization of net actuarial losses	[3]	409	229	819	459
Amortization of net prior service credits, before tax	[3]	0	(4)	0	(8)
Amortization of net prior service credits, tax	[3]	0	(1)	0	(2)
Amortization of net prior service credits	[3]	0	(3)	0	(6)
Net change in defined benefit plan obligations, before tax		535	296	1,071	592
Net change in defined benefit plan obligations, tax		126	70	252	139
Net change in defined benefit plan obligations		409	226	819	453
Total other comprehensive income (loss), before tax		(1,817)	7,369	14,084	21,494
Total other comprehensive income (loss), tax		(426)	1,732	3,309	5,051
Total other comprehensive income (loss), net of tax		$ (1,391)	$ 5,637	$ 10,775	$ 16,443

[1] The pre-tax amount is reported in net realized losses on securities in the Unaudited Consolidated Statements of Income.

[2] 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.

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