Loans, Allowance for Credit Losses and Credit Quality Financing Receivable, Allowance for Credit Loss (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss	$ 92,376	$ 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	1,157
Allowance for Loan and Lease Losses, Write-offs	(734)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	350
Provision for Loan and Lease Losses	25,000
Commercial And Industrial [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss	21,649	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	0
Allowance for Loan and Lease Loss, Recovery of Bad Debts	42
Provision for Loan and Lease Losses	5,948
Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss	29,498	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	0
Provision for Loan and Lease Losses	9,274
Construction Loans [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss	3,747	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	1,346
Small Business [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss	3,829	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	(109)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	3
Provision for Loan and Lease Losses	1,694
Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss	14,847	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	1,155
Home Equity Line of Credit [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss	17,910	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	(138)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	58
Provision for Loan and Lease Losses	5,083
Consumer - Other [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss	896	$ 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	(487)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	246
Provision for Loan and Lease Losses	$ 500