Loans (Changes in the Allowance for Credit Losses) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance	$ 52,420	$ 30,482
Allowance for loan losses, Charge-offs	(2,864)	(12,032)
Allowance for loan losses, Recoveries	1,977	1,889
Allowance for loan losses, Provision (benefit)	(1,705)	13,423
Allowance for loan losses, Ending balance	49,828	43,356
Cumulative-Effect Adjustment [Member] \| ASU 2016-13 [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance		9,594
Adjusted Balance [Member] \| ASU 2016-13 [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance		40,076
Commercial Business [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance	13,580	11,358
Allowance for loan losses, Charge-offs	(86)	(8,241)
Allowance for loan losses, Recoveries	238	58
Allowance for loan losses, Provision (benefit)	(1,062)	7,294
Allowance for loan losses, Ending balance	12,670	10,223
Commercial Business [Member] \| Cumulative-Effect Adjustment [Member] \| ASU 2016-13 [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance		(246)
Commercial Business [Member] \| Adjusted Balance [Member] \| ASU 2016-13 [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance		11,112
Commercial Mortgage [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance	21,763	5,681
Allowance for loan losses, Charge-offs	(203)	0
Allowance for loan losses, Recoveries	0	0
Allowance for loan losses, Provision (benefit)	1,112	2,163
Allowance for loan losses, Ending balance	22,672	15,154
Commercial Mortgage [Member] \| Cumulative-Effect Adjustment [Member] \| ASU 2016-13 [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance		7,310
Commercial Mortgage [Member] \| Adjusted Balance [Member] \| ASU 2016-13 [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance		12,991
Residential Real Estate Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance	3,924	1,059
Allowance for loan losses, Charge-offs	(11)	(98)
Allowance for loan losses, Recoveries	5	10
Allowance for loan losses, Provision (benefit)	(809)	1,909
Allowance for loan losses, Ending balance	3,109	6,170
Residential Real Estate Loans [Member] \| Cumulative-Effect Adjustment [Member] \| ASU 2016-13 [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance		3,290
Residential Real Estate Loans [Member] \| Adjusted Balance [Member] \| ASU 2016-13 [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance		4,349
Residential Real Estate Lines [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance	674	118
Allowance for loan losses, Charge-offs	(70)	0
Allowance for loan losses, Recoveries	0	3
Allowance for loan losses, Provision (benefit)	(122)	171
Allowance for loan losses, Ending balance	482	899
Residential Real Estate Lines [Member] \| Cumulative-Effect Adjustment [Member] \| ASU 2016-13 [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance		607
Residential Real Estate Lines [Member] \| Adjusted Balance [Member] \| ASU 2016-13 [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance		725
Consumer Indirect [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance	12,165	11,852
Allowance for loan losses, Charge-offs	(2,413)	(3,424)
Allowance for loan losses, Recoveries	1,670	1,668
Allowance for loan losses, Provision (benefit)	(865)	1,783
Allowance for loan losses, Ending balance	10,557	10,645
Consumer Indirect [Member] \| Cumulative-Effect Adjustment [Member] \| ASU 2016-13 [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance		(1,234)
Consumer Indirect [Member] \| Adjusted Balance [Member] \| ASU 2016-13 [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance		10,618
Other Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance	314	414
Allowance for loan losses, Charge-offs	(81)	(269)
Allowance for loan losses, Recoveries	64	150
Allowance for loan losses, Provision (benefit)	41	103
Allowance for loan losses, Ending balance	$ 338	265
Other Consumer [Member] \| Cumulative-Effect Adjustment [Member] \| ASU 2016-13 [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance		(133)
Other Consumer [Member] \| Adjusted Balance [Member] \| ASU 2016-13 [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance		$ 281

Financing receivable allowance for loan losses, provision (credit).

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- Definition

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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No definition available.

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Amount of increase in allowance for credit loss on financing receivable from recovery.

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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