Loans Receivable, Net - Aging Analysis (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	$ 15,954,962	$ 15,246,812
Accruing loans 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	19,957	16,331
Accruing loans 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	4,906	4,636
Accruing loans 90 days or more past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	3,876	1,559
Past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	56,833	53,677
Non-accrual loans with no ACL	27,920	31,036
Non-accrual loans with ACL	174	115
Current loans receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	15,898,129	15,193,135
Residential real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	1,588,175	1,446,008
Residential real estate | Accruing loans 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	254	2,796
Residential real estate | Accruing loans 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	636	142
Residential real estate | Accruing loans 90 days or more past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	109	215
Residential real estate | Past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	3,684	5,389
Non-accrual loans with no ACL	2,685	2,236
Non-accrual loans with ACL	0	0
Residential real estate | Current loans receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	1,584,491	1,440,619
Commercial real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	10,220,751	9,797,047
Commercial real estate | Accruing loans 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	13,701	5,462
Commercial real estate | Accruing loans 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	2,393	2,865
Commercial real estate | Accruing loans 90 days or more past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	2,454	472
Commercial real estate | Past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	40,325	31,742
Non-accrual loans with no ACL	21,777	22,943
Non-accrual loans with ACL	0	0
Commercial real estate | Current loans receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	10,180,426	9,765,305
Other commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	2,888,810	2,799,668
Other commercial | Accruing loans 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	1,958	4,192
Other commercial | Accruing loans 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	600	297
Other commercial | Accruing loans 90 days or more past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	826	542
Other commercial | Past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	4,774	8,877
Non-accrual loans with no ACL	1,356	3,790
Non-accrual loans with ACL	34	56
Other commercial | Current loans receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	2,884,036	2,790,791
Home equity
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	862,240	822,232
Home equity | Accruing loans 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	1,556	754
Home equity | Accruing loans 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	472	529
Home equity | Accruing loans 90 days or more past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	211	138
Home equity | Past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	3,548	2,655
Non-accrual loans with no ACL	1,309	1,234
Non-accrual loans with ACL	0	0
Home equity | Current loans receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	858,692	819,577
Other consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	394,986	381,857
Other consumer | Accruing loans 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	2,488	3,127
Other consumer | Accruing loans 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	805	803
Other consumer | Accruing loans 90 days or more past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	276	192
Other consumer | Past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	4,502	5,014
Non-accrual loans with no ACL	793	833
Non-accrual loans with ACL	140	59
Other consumer | Current loans receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	$ 390,484	$ 376,843