Allowance for Credit Losses - Loans on Nonaccrual Status and Loans Past Due 90 Days or More and Still Accruing (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020 USD ($)	Sep. 30, 2020 USD ($)
Financing Receivable, Nonaccrual [Line Items]
Beginning of Period Nonaccrual		$ 54,057
End of Period Nonaccrual	$ 84,072	84,072
Nonaccrual With No Related Allowance	34,776	34,776
Past Due 90+ Days Still Accruing	520	520
Interest income recognized on nonaccrual	189	500
Commercial \| Commercial real estate
Financing Receivable, Nonaccrual [Line Items]
Beginning of Period Nonaccrual		25,356
End of Period Nonaccrual	47,095	47,095
Nonaccrual With No Related Allowance	26,996	26,996
Past Due 90+ Days Still Accruing	0	0
Interest income recognized on nonaccrual	8	19
Commercial \| Commercial and industrial
Financing Receivable, Nonaccrual [Line Items]
Beginning of Period Nonaccrual		10,911
End of Period Nonaccrual	5,686	5,686
Nonaccrual With No Related Allowance	967	967
Past Due 90+ Days Still Accruing	386	386
Interest income recognized on nonaccrual	31	52
Commercial \| Commercial construction
Financing Receivable, Nonaccrual [Line Items]
Beginning of Period Nonaccrual		737
End of Period Nonaccrual	1,504	1,504
Nonaccrual With No Related Allowance	1,218	1,218
Past Due 90+ Days Still Accruing	0	0
Interest income recognized on nonaccrual	0	0
Commercial \| Business banking
Financing Receivable, Nonaccrual [Line Items]
Beginning of Period Nonaccrual		9,863
End of Period Nonaccrual	18,081	18,081
Nonaccrual With No Related Allowance	5,197	5,197
Past Due 90+ Days Still Accruing	0	0
Interest income recognized on nonaccrual	59	163
Consumer \| Consumer real estate
Financing Receivable, Nonaccrual [Line Items]
Beginning of Period Nonaccrual		6,063
End of Period Nonaccrual	9,810	9,810
Nonaccrual With No Related Allowance	398	398
Past Due 90+ Days Still Accruing	134	134
Interest income recognized on nonaccrual	90	262
Consumer \| Other consumer
Financing Receivable, Nonaccrual [Line Items]
Beginning of Period Nonaccrual		1,127
End of Period Nonaccrual	1,896	1,896
Nonaccrual With No Related Allowance	0	0
Past Due 90+ Days Still Accruing	0	0
Interest income recognized on nonaccrual	$ 1	$ 4

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No definition available.

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