Loans Receivable, Net - Aging Analysis (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	$ 14,399,755	$ 13,432,031
Accruing loans 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	13,650	38,081
Accruing loans 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	2,938	12,485
Accruing loans 90 days or more past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	5,064	17,141
Past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	60,175	118,239
Non-accrual loans with no ACL	36,136	28,961
Non-accrual loans with ACL	2,387	21,571
Current loans receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	14,339,580	13,313,792
Residential real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	1,261,119	1,051,883
Residential real estate | Accruing loans 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	1,580	2,132
Residential real estate | Accruing loans 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	98	457
Residential real estate | Accruing loans 90 days or more past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	60	223
Residential real estate | Past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	3,550	5,229
Non-accrual loans with no ACL	1,812	2,162
Non-accrual loans with ACL	0	255
Residential real estate | Current loans receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	1,257,569	1,046,654
Commercial real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	9,310,070	8,630,831
Commercial real estate | Accruing loans 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	3,151	26,063
Commercial real estate | Accruing loans 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	1,258	9,537
Commercial real estate | Accruing loans 90 days or more past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	2,542	15,345
Commercial real estate | Past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	34,593	71,433
Non-accrual loans with no ACL	27,642	20,040
Non-accrual loans with ACL	0	448
Commercial real estate | Current loans receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	9,275,477	8,559,398
Other commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	2,685,392	2,664,190
Other commercial | Accruing loans 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	6,028	5,464
Other commercial | Accruing loans 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	664	1,652
Other commercial | Accruing loans 90 days or more past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	2,079	1,383
Other commercial | Past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	15,889	33,827
Non-accrual loans with no ACL	4,737	4,563
Non-accrual loans with ACL	2,381	20,765
Other commercial | Current loans receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	2,669,503	2,630,363
Home equity
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	773,582	736,288
Home equity | Accruing loans 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	795	1,582
Home equity | Accruing loans 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	341	512
Home equity | Accruing loans 90 days or more past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	184	57
Home equity | Past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	2,851	3,962
Non-accrual loans with no ACL	1,531	1,712
Non-accrual loans with ACL	0	99
Home equity | Current loans receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	770,731	732,326
Other consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	369,592	348,839
Other consumer | Accruing loans 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	2,096	2,840
Other consumer | Accruing loans 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	577	327
Other consumer | Accruing loans 90 days or more past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	199	133
Other consumer | Past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	3,292	3,788
Non-accrual loans with no ACL	414	484
Non-accrual loans with ACL	6	4
Other consumer | Current loans receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	$ 366,300	$ 345,051