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Loans, Allowance for Credit Losses and Credit Quality Financing Receivable, Allowance for Credit Loss (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss	$ 107,549		$ 113,392	$ 67,740
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method		$ (1,137)
Financing Receivable, Allowance for Credit Loss, Purchased with Credit Deterioration, Increase	1,200	1,157
Allowance for Loan and Lease Losses, Write-offs	(3,686)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	343
Provision for Loan and Lease Losses	(2,500)
Loans and Leases Receivable, Allowance	107,549	92,376	113,392
Provision for credit losses	(2,500)	25,000
Allowance for Loan and Lease Loss, Recovery of Bad Debts		350
Allowance for Loan and Lease Losses, Write-offs		(734)
Commercial And Industrial [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss	20,207		21,086	17,594
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method		(1,984)
Financing Receivable, Allowance for Credit Loss, Purchased with Credit Deterioration, Increase		49
Allowance for Loan and Lease Losses, Write-offs	(3,331)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	64
Provision for Loan and Lease Losses	2,388
Loans and Leases Receivable, Allowance		21,649
Provision for credit losses		5,948
Allowance for Loan and Lease Loss, Recovery of Bad Debts		42
Allowance for Loan and Lease Losses, Write-offs		0
Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss	44,348		45,009	32,935
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method		(13,048)
Financing Receivable, Allowance for Credit Loss, Purchased with Credit Deterioration, Increase		337
Allowance for Loan and Lease Losses, Write-offs	0
Allowance for Loan and Lease Loss, Recovery of Bad Debts	57
Provision for Loan and Lease Losses	(718)
Loans and Leases Receivable, Allowance		29,498
Provision for credit losses		9,274
Allowance for Loan and Lease Loss, Recovery of Bad Debts		0
Allowance for Loan and Lease Losses, Write-offs		0
Construction Loans [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss	5,268		5,397	6,053
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method		(3,652)
Financing Receivable, Allowance for Credit Loss, Purchased with Credit Deterioration, Increase		0
Allowance for Loan and Lease Losses, Write-offs	0
Allowance for Loan and Lease Loss, Recovery of Bad Debts	0
Provision for Loan and Lease Losses	(129)
Loans and Leases Receivable, Allowance		3,747
Provision for credit losses		1,346
Allowance for Loan and Lease Loss, Recovery of Bad Debts		0
Allowance for Loan and Lease Losses, Write-offs		0
Small Business [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss	3,621		5,095	1,746
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method		495
Financing Receivable, Allowance for Credit Loss, Purchased with Credit Deterioration, Increase		0
Allowance for Loan and Lease Losses, Write-offs	(66)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	11
Provision for Loan and Lease Losses	(1,419)
Loans and Leases Receivable, Allowance		3,829
Provision for credit losses		1,694
Allowance for Loan and Lease Loss, Recovery of Bad Debts		3
Allowance for Loan and Lease Losses, Write-offs		(109)
Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss	12,956		14,275	3,440
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method		9,828
Financing Receivable, Allowance for Credit Loss, Purchased with Credit Deterioration, Increase		423
Allowance for Loan and Lease Losses, Write-offs	0
Allowance for Loan and Lease Loss, Recovery of Bad Debts	1
Provision for Loan and Lease Losses	(1,320)
Loans and Leases Receivable, Allowance		14,847
Provision for credit losses		1,155
Allowance for Loan and Lease Loss, Recovery of Bad Debts		1
Allowance for Loan and Lease Losses, Write-offs		0
Home Equity Line of Credit [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss	20,716		22,060	5,576
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method		7,012
Financing Receivable, Allowance for Credit Loss, Purchased with Credit Deterioration, Increase		319
Allowance for Loan and Lease Losses, Write-offs	0
Allowance for Loan and Lease Loss, Recovery of Bad Debts	13
Provision for Loan and Lease Losses	(1,357)
Loans and Leases Receivable, Allowance		17,910
Provision for credit losses		5,083
Allowance for Loan and Lease Loss, Recovery of Bad Debts		58
Allowance for Loan and Lease Losses, Write-offs		(138)
Consumer - Other [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss	433		$ 470	$ 396
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method		212
Financing Receivable, Allowance for Credit Loss, Purchased with Credit Deterioration, Increase		29
Allowance for Loan and Lease Losses, Write-offs	(289)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	197
Provision for Loan and Lease Losses	$ 55
Loans and Leases Receivable, Allowance		896
Provision for credit losses		500
Allowance for Loan and Lease Loss, Recovery of Bad Debts		246
Allowance for Loan and Lease Losses, Write-offs		$ (487)