Allowance for Credit Losses - Loans on Nonaccrual Status and Loans Past Due 90 Days or More and Still Accruing (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2021	Jun. 30, 2021	Dec. 31, 2020
Financing Receivable, Nonaccrual [Line Items]
Beginning of Period Nonaccrual		$ 146,774	$ 54,057
End of Period Nonaccrual	$ 112,619	112,619	146,774
Nonaccrual With No Related Allowance	60,340	60,340	71,410
Past Due 90+ Days Still Accruing			503
Interest income recognized on nonaccrual	426	776	826
Commercial \| Commercial real estate
Financing Receivable, Nonaccrual [Line Items]
Beginning of Period Nonaccrual		101,070	25,356
End of Period Nonaccrual	80,067	80,067	101,070
Nonaccrual With No Related Allowance	47,648	47,648	60,401
Past Due 90+ Days Still Accruing			0
Interest income recognized on nonaccrual	5	66	22
Commercial \| Commercial and industrial
Financing Receivable, Nonaccrual [Line Items]
Beginning of Period Nonaccrual		16,985	10,911
End of Period Nonaccrual	12,198	12,198	16,985
Nonaccrual With No Related Allowance	11,183	11,183	6,436
Past Due 90+ Days Still Accruing			0
Interest income recognized on nonaccrual	72	115	101
Commercial \| Commercial construction
Financing Receivable, Nonaccrual [Line Items]
Beginning of Period Nonaccrual		384	737
End of Period Nonaccrual	385	385	384
Nonaccrual With No Related Allowance	0	0	285
Past Due 90+ Days Still Accruing			0
Interest income recognized on nonaccrual	0	0	0
Commercial \| Business banking
Financing Receivable, Nonaccrual [Line Items]
Beginning of Period Nonaccrual		17,122	9,863
End of Period Nonaccrual	11,064	11,064	17,122
Nonaccrual With No Related Allowance	1,508	1,508	3,890
Past Due 90+ Days Still Accruing			371
Interest income recognized on nonaccrual	139	275	275
Consumer \| Consumer real estate
Financing Receivable, Nonaccrual [Line Items]
Beginning of Period Nonaccrual		11,117	6,063
End of Period Nonaccrual	8,783	8,783	11,117
Nonaccrual With No Related Allowance	0	0	398
Past Due 90+ Days Still Accruing			132
Interest income recognized on nonaccrual	210	319	423
Consumer \| Other consumer
Financing Receivable, Nonaccrual [Line Items]
Beginning of Period Nonaccrual		96	1,127
End of Period Nonaccrual	121	121	96
Nonaccrual With No Related Allowance	0	0	0
Past Due 90+ Days Still Accruing			0
Interest income recognized on nonaccrual	$ 0	$ 1	$ 4

Amount of interest income on financing receivable on nonaccrual status.

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Amount of financing receivable 90 days or more past due and still accruing.

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