Loans, Allowance for Credit Losses and Credit Quality Financing Receivable, Allowance for Credit Loss (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2019
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss	$ 102,357		$ 102,357		$ 107,549	$ 67,740	$ 92,376	$ 113,392
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method				$ (1,137)
Financing Receivable, Allowance for Credit Loss, Purchased with Credit Deterioration, Increase				1,157
Allowance for Loan and Lease Losses, Write-offs	(481)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	289
Provision for Loan and Lease Losses	(5,000)
Loans and Leases Receivable, Allowance	102,357	$ 112,176	102,357	112,176		113,392
Provision for credit losses	(5,000)	20,000	(7,500)	45,000
Allowance for Loan and Lease Loss, Recovery of Bad Debts		510	632	860
Allowance for Loan and Lease Losses, Write-offs		(710)	(4,167)	(1,444)
Commercial And Industrial [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss	17,032		17,032		20,207	17,594	21,649	21,086
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	(142)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	35
Provision for Loan and Lease Losses	(3,068)
Loans and Leases Receivable, Allowance	17,032	25,662	17,032	25,662
Provision for credit losses		4,009	(680)	9,957
Allowance for Loan and Lease Loss, Recovery of Bad Debts		4	99	46
Allowance for Loan and Lease Losses, Write-offs		0	(3,473)	0
Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss	44,325		44,325		44,348	32,935	29,498	45,009
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	0
Provision for Loan and Lease Losses	(23)
Loans and Leases Receivable, Allowance	44,325	36,956	44,325	36,956
Provision for credit losses		7,458	(741)	16,732
Allowance for Loan and Lease Loss, Recovery of Bad Debts		0	57	0
Allowance for Loan and Lease Losses, Write-offs		0	0	0
Construction Loans [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss	4,865		4,865		5,268	6,053	3,747	5,397
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	(403)
Loans and Leases Receivable, Allowance	4,865	4,501	4,865	4,501
Provision for credit losses		754	(532)	2,100
Allowance for Loan and Lease Loss, Recovery of Bad Debts		0	0	0
Allowance for Loan and Lease Losses, Write-offs		0	0	0
Small Business [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss	3,612		3,612		3,621	1,746	3,829	5,095
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	(35)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	4
Provision for Loan and Lease Losses	22
Loans and Leases Receivable, Allowance	3,612	4,561	3,612	4,561
Provision for credit losses		765	(1,397)	2,459
Allowance for Loan and Lease Loss, Recovery of Bad Debts		3	15	6
Allowance for Loan and Lease Losses, Write-offs		(36)	(101)	(145)
Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss	12,014		12,014		12,956	3,440	14,847	14,275
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	0
Provision for Loan and Lease Losses	(942)
Loans and Leases Receivable, Allowance	12,014	15,046	12,014	15,046
Provision for credit losses		199	(2,262)	1,354
Allowance for Loan and Lease Loss, Recovery of Bad Debts		0	1	1
Allowance for Loan and Lease Losses, Write-offs		0	0	0
Home Equity Line of Credit [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss	20,087		20,087		20,716	5,576	17,910	22,060
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	(69)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	45
Provision for Loan and Lease Losses	(605)
Loans and Leases Receivable, Allowance	20,087	24,860	20,087	24,860
Provision for credit losses		6,859	(1,962)	11,942
Allowance for Loan and Lease Loss, Recovery of Bad Debts		95	58	153
Allowance for Loan and Lease Losses, Write-offs		(4)	(69)	(142)
Consumer - Other [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss	422		422		$ 433	$ 396	$ 896	$ 470
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	(235)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	205
Provision for Loan and Lease Losses	19
Loans and Leases Receivable, Allowance	$ 422	590	422	590
Provision for credit losses		(44)	74	456
Allowance for Loan and Lease Loss, Recovery of Bad Debts		408	402	654
Allowance for Loan and Lease Losses, Write-offs		$ (670)	$ (524)	$ (1,157)