Loans Receivable Aging Analysis (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Loan portfolio aging analysis
Non-accrual loans with no ACL	$ 25,219
Non-accrual loans with ACL	2,787
Non-accrual loans		$ 30,883
Total past due and non-accrual loans	76,005	55,487
Current loans receivable	10,012,201	9,457,323
Total loans receivable	10,088,206	9,512,810
Accruing loans 30 to 59 days past due
Loan portfolio aging analysis
Accruing loans past due	31,688	15,944
Accruing loans 60 to 89 days past due
Loan portfolio aging analysis
Accruing loans past due	9,687	7,248
Accruing loans 90 days or more past due
Loan portfolio aging analysis
Accruing loans past due	6,624	1,412
Residential Real Estate
Loan portfolio aging analysis
Non-accrual loans with no ACL	4,126
Non-accrual loans with ACL	307
Non-accrual loans		4,715
Total past due and non-accrual loans	13,598	9,620
Current loans receivable	944,232	916,768
Total loans receivable	957,830	926,388
Residential Real Estate \| Accruing loans 30 to 59 days past due
Loan portfolio aging analysis
Accruing loans past due	8,419	3,403
Residential Real Estate \| Accruing loans 60 to 89 days past due
Loan portfolio aging analysis
Accruing loans past due	45	749
Residential Real Estate \| Accruing loans 90 days or more past due
Loan portfolio aging analysis
Accruing loans past due	701	753
Commercial Real Estate
Loan portfolio aging analysis
Non-accrual loans with no ACL	11,328
Non-accrual loans with ACL	2,137
Non-accrual loans		15,650
Total past due and non-accrual loans	29,992	22,977
Current loans receivable	5,898,311	5,556,330
Total loans receivable	5,928,303	5,579,307
Commercial Real Estate \| Accruing loans 30 to 59 days past due
Loan portfolio aging analysis
Accruing loans past due	9,516	4,946
Commercial Real Estate \| Accruing loans 60 to 89 days past due
Loan portfolio aging analysis
Accruing loans past due	3,311	2,317
Commercial Real Estate \| Accruing loans 90 days or more past due
Loan portfolio aging analysis
Accruing loans past due	3,700	64
Other Commercial
Loan portfolio aging analysis
Non-accrual loans with no ACL	6,395
Non-accrual loans with ACL	257
Non-accrual loans		6,592
Total past due and non-accrual loans	19,908	12,610
Current loans receivable	2,219,970	2,081,644
Total loans receivable	2,239,878	2,094,254
Other Commercial \| Accruing loans 30 to 59 days past due
Loan portfolio aging analysis
Accruing loans past due	7,791	4,685
Other Commercial \| Accruing loans 60 to 89 days past due
Loan portfolio aging analysis
Accruing loans past due	3,727	1,190
Other Commercial \| Accruing loans 90 days or more past due
Loan portfolio aging analysis
Accruing loans past due	1,738	143
Home Equity
Loan portfolio aging analysis
Non-accrual loans with no ACL	2,953
Non-accrual loans with ACL	50
Non-accrual loans		3,266
Total past due and non-accrual loans	8,828	6,208
Current loans receivable	644,114	610,993
Total loans receivable	652,942	617,201
Home Equity \| Accruing loans 30 to 59 days past due
Loan portfolio aging analysis
Accruing loans past due	3,808	1,040
Home Equity \| Accruing loans 60 to 89 days past due
Loan portfolio aging analysis
Accruing loans past due	1,877	1,902
Home Equity \| Accruing loans 90 days or more past due
Loan portfolio aging analysis
Accruing loans past due	140	0
Other Consumer
Loan portfolio aging analysis
Non-accrual loans with no ACL	417
Non-accrual loans with ACL	36
Non-accrual loans		660
Total past due and non-accrual loans	3,679	4,072
Current loans receivable	305,574	291,588
Total loans receivable	309,253	295,660
Other Consumer \| Accruing loans 30 to 59 days past due
Loan portfolio aging analysis
Accruing loans past due	2,154	1,870
Other Consumer \| Accruing loans 60 to 89 days past due
Loan portfolio aging analysis
Accruing loans past due	727	1,090
Other Consumer \| Accruing loans 90 days or more past due
Loan portfolio aging analysis
Accruing loans past due	$ 345	$ 452

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

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Financing receivable recorded investment past due and non accrual loans.

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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 on nonaccrual status.

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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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