Loans Receivable, Net - Aging Analysis (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	$ 15,518,612	$ 15,246,812
Accruing loans 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	17,031	16,331
Accruing loans 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	7,962	4,636
Accruing loans 90 days or more past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	3,545	1,559
Past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	56,941	53,677
Non-accrual loans with no ACL	28,153	31,036
Non-accrual loans with ACL	250	115
Current loans receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	15,461,671	15,193,135
Residential real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	1,508,403	1,446,008
Residential real estate | Accruing loans 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	4,338	2,796
Residential real estate | Accruing loans 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	140	142
Residential real estate | Accruing loans 90 days or more past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	54	215
Residential real estate | Past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	6,568	5,389
Non-accrual loans with no ACL	2,036	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	1,501,835	1,440,619
Commercial real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	9,992,019	9,797,047
Commercial real estate | Accruing loans 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	3,842	5,462
Commercial real estate | Accruing loans 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	5,432	2,865
Commercial real estate | Accruing loans 90 days or more past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	2,623	472
Commercial real estate | Past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	33,863	31,742
Non-accrual loans with no ACL	21,966	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	9,958,156	9,765,305
Other commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	2,804,104	2,799,668
Other commercial | Accruing loans 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	3,559	4,192
Other commercial | Accruing loans 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	988	297
Other commercial | Accruing loans 90 days or more past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	475	542
Other commercial | Past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	7,200	8,877
Non-accrual loans with no ACL	2,109	3,790
Non-accrual loans with ACL	69	56
Other commercial | Current loans receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	2,796,904	2,790,791
Home equity
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	829,844	822,232
Home equity | Accruing loans 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	2,354	754
Home equity | Accruing loans 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	751	529
Home equity | Accruing loans 90 days or more past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	194	138
Home equity | Past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	4,526	2,655
Non-accrual loans with no ACL	1,227	1,234
Non-accrual loans with ACL	0	0
Home equity | Current loans receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	825,318	819,577
Other consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	384,242	381,857
Other consumer | Accruing loans 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	2,938	3,127
Other consumer | Accruing loans 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	651	803
Other consumer | Accruing loans 90 days or more past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	199	192
Other consumer | Past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	4,784	5,014
Non-accrual loans with no ACL	815	833
Non-accrual loans with ACL	181	59
Other consumer | Current loans receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	$ 379,458	$ 376,843