Loans Receivable, Net - Aging Analysis (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Loan portfolio aging analysis
Non-accrual loans with no ACL	$ 32,047
Non-accrual loans with ACL	4,303
Non-accrual loans		$ 30,883
Total past due and non-accrual loans	56,933	55,487
Current loans receivable	11,561,798	9,457,323
Total loans receivable	11,618,731	9,512,810
Accruing loans 30-59 days past due
Loan portfolio aging analysis
Accruing loans past due	9,534	15,944
Accruing loans 60-89 days past due
Loan portfolio aging analysis
Accruing loans past due	8,097	7,248
Accruing loans 90 days or more past due
Loan portfolio aging analysis
Accruing loans past due	2,952	1,412
Residential Real Estate
Loan portfolio aging analysis
Non-accrual loans with no ACL	3,213
Non-accrual loans with ACL	275
Non-accrual loans		4,715
Total past due and non-accrual loans	5,891	9,620
Current loans receivable	856,723	916,768
Total loans receivable	862,614	926,388
Residential Real Estate \| Accruing loans 30-59 days past due
Loan portfolio aging analysis
Accruing loans past due	520	3,403
Residential Real Estate \| Accruing loans 60-89 days past due
Loan portfolio aging analysis
Accruing loans past due	1,666	749
Residential Real Estate \| Accruing loans 90 days or more past due
Loan portfolio aging analysis
Accruing loans past due	217	753
Commercial Real Estate
Loan portfolio aging analysis
Non-accrual loans with no ACL	16,318
Non-accrual loans with ACL	1,980
Non-accrual loans		15,650
Total past due and non-accrual loans	25,340	22,977
Current loans receivable	6,176,477	5,556,330
Total loans receivable	6,201,817	5,579,307
Commercial Real Estate \| Accruing loans 30-59 days past due
Loan portfolio aging analysis
Accruing loans past due	2,662	4,946
Commercial Real Estate \| Accruing loans 60-89 days past due
Loan portfolio aging analysis
Accruing loans past due	2,954	2,317
Commercial Real Estate \| Accruing loans 90 days or more past due
Loan portfolio aging analysis
Accruing loans past due	1,426	64
Other Commercial
Loan portfolio aging analysis
Non-accrual loans with no ACL	9,441
Non-accrual loans with ACL	1,930
Non-accrual loans		6,592
Total past due and non-accrual loans	17,518	12,610
Current loans receivable	3,575,804	2,081,644
Total loans receivable	3,593,322	2,094,254
Other Commercial \| Accruing loans 30-59 days past due
Loan portfolio aging analysis
Accruing loans past due	2,782	4,685
Other Commercial \| Accruing loans 60-89 days past due
Loan portfolio aging analysis
Accruing loans past due	2,263	1,190
Other Commercial \| Accruing loans 90 days or more past due
Loan portfolio aging analysis
Accruing loans past due	1,102	143
Home Equity
Loan portfolio aging analysis
Non-accrual loans with no ACL	2,804
Non-accrual loans with ACL	87
Non-accrual loans		3,266
Total past due and non-accrual loans	6,108	6,208
Current loans receivable	640,742	610,993
Total loans receivable	646,850	617,201
Home Equity \| Accruing loans 30-59 days past due
Loan portfolio aging analysis
Accruing loans past due	2,160	1,040
Home Equity \| Accruing loans 60-89 days past due
Loan portfolio aging analysis
Accruing loans past due	977	1,902
Home Equity \| Accruing loans 90 days or more past due
Loan portfolio aging analysis
Accruing loans past due	80	0
Other Consumer
Loan portfolio aging analysis
Non-accrual loans with no ACL	271
Non-accrual loans with ACL	31
Non-accrual loans		660
Total past due and non-accrual loans	2,076	4,072
Current loans receivable	312,052	291,588
Total loans receivable	314,128	295,660
Other Consumer \| Accruing loans 30-59 days past due
Loan portfolio aging analysis
Accruing loans past due	1,410	1,870
Other Consumer \| Accruing loans 60-89 days past due
Loan portfolio aging analysis
Accruing loans past due	237	1,090
Other Consumer \| Accruing loans 90 days or more past due
Loan portfolio aging analysis
Accruing loans past due	$ 127	$ 452

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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 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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