Loans Receivable, Net - Aging Analysis (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Loan portfolio aging analysis
Non-accrual loans with no ACL	$ 29,532
Non-accrual loans with ACL	2,432
Non-accrual loans		$ 30,883
Total past due and non-accrual loans	56,410	55,487
Current loans receivable	11,066,286	9,457,323
Total loans receivable	11,122,696	9,512,810
Accruing loans 30 to 59 days past due
Loan portfolio aging analysis
Past due loans	17,123	15,944
Accruing loans 60 to 89 days past due
Loan portfolio aging analysis
Past due loans	5,598	7,248
Accruing loans 90 days or more past due
Loan portfolio aging analysis
Past due loans	1,725	1,412
Residential Real Estate
Loan portfolio aging analysis
Non-accrual loans with no ACL	3,129
Non-accrual loans with ACL	274
Non-accrual loans		4,715
Total past due and non-accrual loans	10,979	9,620
Current loans receivable	791,529	916,768
Total loans receivable	802,508	926,388
Residential Real Estate \| Accruing loans 30 to 59 days past due
Loan portfolio aging analysis
Past due loans	6,058	3,403
Residential Real Estate \| Accruing loans 60 to 89 days past due
Loan portfolio aging analysis
Past due loans	584	749
Residential Real Estate \| Accruing loans 90 days or more past due
Loan portfolio aging analysis
Past due loans	934	753
Commercial Real Estate
Loan portfolio aging analysis
Non-accrual loans with no ACL	14,030
Non-accrual loans with ACL	1,787
Non-accrual loans		15,650
Total past due and non-accrual loans	22,201	22,977
Current loans receivable	6,293,694	5,556,330
Total loans receivable	6,315,895	5,579,307
Commercial Real Estate \| Accruing loans 30 to 59 days past due
Loan portfolio aging analysis
Past due loans	3,854	4,946
Commercial Real Estate \| Accruing loans 60 to 89 days past due
Loan portfolio aging analysis
Past due loans	2,299	2,317
Commercial Real Estate \| Accruing loans 90 days or more past due
Loan portfolio aging analysis
Past due loans	231	64
Other Commercial
Loan portfolio aging analysis
Non-accrual loans with no ACL	9,231
Non-accrual loans with ACL	278
Non-accrual loans		6,592
Total past due and non-accrual loans	14,650	12,610
Current loans receivable	3,040,167	2,081,644
Total loans receivable	3,054,817	2,094,254
Other Commercial \| Accruing loans 30 to 59 days past due
Loan portfolio aging analysis
Past due loans	4,039	4,685
Other Commercial \| Accruing loans 60 to 89 days past due
Loan portfolio aging analysis
Past due loans	809	1,190
Other Commercial \| Accruing loans 90 days or more past due
Loan portfolio aging analysis
Past due loans	293	143
Home Equity
Loan portfolio aging analysis
Non-accrual loans with no ACL	2,664
Non-accrual loans with ACL	49
Non-accrual loans		3,266
Total past due and non-accrual loans	5,734	6,208
Current loans receivable	630,671	610,993
Total loans receivable	636,405	617,201
Home Equity \| Accruing loans 30 to 59 days past due
Loan portfolio aging analysis
Past due loans	2,130	1,040
Home Equity \| Accruing loans 60 to 89 days past due
Loan portfolio aging analysis
Past due loans	756	1,902
Home Equity \| Accruing loans 90 days or more past due
Loan portfolio aging analysis
Past due loans	135	0
Consumer and Other
Loan portfolio aging analysis
Non-accrual loans with no ACL	478
Non-accrual loans with ACL	44
Non-accrual loans		660
Total past due and non-accrual loans	2,846	4,072
Current loans receivable	310,225	291,588
Total loans receivable	313,071	295,660
Consumer and Other \| Accruing loans 30 to 59 days past due
Loan portfolio aging analysis
Past due loans	1,042	1,870
Consumer and Other \| Accruing loans 60 to 89 days past due
Loan portfolio aging analysis
Past due loans	1,150	1,090
Consumer and Other \| Accruing loans 90 days or more past due
Loan portfolio aging analysis
Past due loans	$ 132	$ 452

Amount of financing receivable on nonaccrual status with allowance for credit loss.

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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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