Other Comprehensive Income (Loss) (Activity in Other Comprehensive Income) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019		Dec. 31, 2018	Dec. 31, 2017
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent [Abstract]
Change in fair value of securities available for sale, before tax		$ 26,074		$ (12,063)	$ 986
Change in fair value of securities available for sale, tax		6,127		(2,835)	365
Change is fair value of securities available for sale		19,947		(9,228)	621
Net (gains) losses on securities classified into earnings, before tax		53	[1]	0	0
Net (gains) losses on securities classified into earnings, tax		12	[1]	0	0
Net (gains) losses on securities classified into earnings		41	[1]	0	0
Net change in fair value of securities available for sale, before tax		26,127		(12,063)	986
Net change in fair value of securities available for sale, tax		6,139		(2,835)	365
Net change in fair value of securities available for sale		19,988		(9,228)	621
Net change in fair value of cash flow hedges, before tax		(1,444)		639	(774)
Net change in fair value of cash flow hedges, tax		(339)		151	(223)
Change in fair value of cash flow hedges		(1,105)		488	(551)
Net cash flow hedge losses reclassified into earnings, before tax	[2]	159		170	792
Net cash flow hedge losses reclassified into earnings, tax	[2]	38		39	293
Net cash flow hedge losses reclassified into earnings	[2]	121		131	499
Change in fair value of cash flow hedges, before tax		(1,285)		809	18
Change in fair value of cash flow hedges, tax		(301)		190	70
Net change in fair value of cash flow hedges		(984)		619	(52)
Defined benefit plan obligation adjustment, before tax		(3,710)		3,098	(1,591)
Defined benefit plan obligation adjustment, tax		(872)		729	(594)
Defined benefit plan obligation adjustment		(2,838)		2,369	(997)
Amortization of net actuarial losses, before tax	[3]	1,200		1,907	1,461
Amortization of net actuarial losses, tax	[3]	282		448	546
Amortization of net actuarial losses	[3]	918		1,459	915
Amortization of net prior service credits, before tax	[3]	(16)		(24)	(24)
Amortization of net prior service credits, tax	[3]	(4)		(6)	(9)
Amortization of net prior service credits	[3]	(12)		(18)	(15)
Net change in defined benefit plan obligations, before tax		(2,526)		4,981	(154)
Net change in defined benefit plan obligations, tax		(594)		1,171	(57)
Net change in defined benefit plan obligations		(1,932)		3,810	(97)
Total other comprehensive income (loss), before tax		22,316		(6,273)	850
Total other comprehensive income (loss), tax		5,244		(1,474)	378
Total other comprehensive income (loss), net of tax		17,072		(4,799)	472
Net Unrealized Gains (Losses) on AFS Securities [Member]
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent [Abstract]
Total other comprehensive income (loss), net of tax		$ 19,988		$ (9,228)	$ 621

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

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