Loans Receivable, Net - Aging Analysis (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Loan portfolio aging analysis
Non-accrual loans with no ACL	$ 28,654	$ 29,532
Non-accrual loans with ACL	1,233
Non-accrual loans with ACL		2,432
Total past due and non-accrual loans	78,236	56,410
Current loans receivable	11,191,693	11,066,286
Total loans receivable	11,269,929	11,122,696
Accruing loans 30-59 days past due
Loan portfolio aging analysis
Accruing loans past due	41,744	17,123
Accruing loans 60-89 days past due
Loan portfolio aging analysis
Accruing loans past due	2,872	5,598
Accruing loans 90 days or more past due
Loan portfolio aging analysis
Accruing loans past due	3,733	1,725
Residential real estate
Loan portfolio aging analysis
Non-accrual loans with no ACL	3,006	3,129
Non-accrual loans with ACL	270
Non-accrual loans with ACL		274
Total past due and non-accrual loans	9,091	10,979
Current loans receivable	736,006	791,529
Total loans receivable	745,097	802,508
Residential real estate \| Accruing loans 30-59 days past due
Loan portfolio aging analysis
Accruing loans past due	5,201	6,058
Residential real estate \| Accruing loans 60-89 days past due
Loan portfolio aging analysis
Accruing loans past due	426	584
Residential real estate \| Accruing loans 90 days or more past due
Loan portfolio aging analysis
Accruing loans past due	188	934
Commercial real estate
Loan portfolio aging analysis
Non-accrual loans with no ACL	13,484	14,030
Non-accrual loans with ACL	451
Non-accrual loans with ACL		1,787
Total past due and non-accrual loans	23,467	22,201
Current loans receivable	6,451,234	6,293,694
Total loans receivable	6,474,701	6,315,895
Commercial real estate \| Accruing loans 30-59 days past due
Loan portfolio aging analysis
Accruing loans past due	5,737	3,854
Commercial real estate \| Accruing loans 60-89 days past due
Loan portfolio aging analysis
Accruing loans past due	1,476	2,299
Commercial real estate \| Accruing loans 90 days or more past due
Loan portfolio aging analysis
Accruing loans past due	2,319	231
Other commercial
Loan portfolio aging analysis
Non-accrual loans with no ACL	8,400	9,231
Non-accrual loans with ACL	423
Non-accrual loans with ACL		278
Total past due and non-accrual loans	38,571	14,650
Current loans receivable	3,062,013	3,040,167
Total loans receivable	3,100,584	3,054,817
Other commercial \| Accruing loans 30-59 days past due
Loan portfolio aging analysis
Accruing loans past due	28,277	4,039
Other commercial \| Accruing loans 60-89 days past due
Loan portfolio aging analysis
Accruing loans past due	510	809
Other commercial \| Accruing loans 90 days or more past due
Loan portfolio aging analysis
Accruing loans past due	961	293
Home equity
Loan portfolio aging analysis
Non-accrual loans with no ACL	2,756	2,664
Non-accrual loans with ACL	49
Non-accrual loans with ACL		49
Total past due and non-accrual loans	4,519	5,734
Current loans receivable	620,850	630,671
Total loans receivable	625,369	636,405
Home equity \| Accruing loans 30-59 days past due
Loan portfolio aging analysis
Accruing loans past due	1,412	2,130
Home equity \| Accruing loans 60-89 days past due
Loan portfolio aging analysis
Accruing loans past due	276	756
Home equity \| Accruing loans 90 days or more past due
Loan portfolio aging analysis
Accruing loans past due	26	135
Other consumer
Loan portfolio aging analysis
Non-accrual loans with no ACL	1,008	478
Non-accrual loans with ACL	40
Non-accrual loans with ACL		44
Total past due and non-accrual loans	2,588	2,846
Current loans receivable	321,590	310,225
Total loans receivable	324,178	313,071
Other consumer \| Accruing loans 30-59 days past due
Loan portfolio aging analysis
Accruing loans past due	1,117	1,042
Other consumer \| Accruing loans 60-89 days past due
Loan portfolio aging analysis
Accruing loans past due	184	1,150
Other consumer \| Accruing loans 90 days or more past due
Loan portfolio aging analysis
Accruing loans past due	$ 239	$ 132

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Amount of financing receivable on nonaccrual status with no allowance for credit loss.

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Amount of financing receivable not past due.

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Amount of financing receivable past due.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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