Loans Receivable, Net - Aging Analysis (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Loan portfolio aging analysis
Loans receivable	$ 13,432,031	$ 11,122,696
Accruing loans 30-59 days past due
Loan portfolio aging analysis
Loans receivable	38,081	17,123
Accruing loans 60-89 days past due
Loan portfolio aging analysis
Loans receivable	12,485	5,598
Accruing loans 90 days or more past due
Loan portfolio aging analysis
Loans receivable	17,141	1,725
Financial Asset, Past Due
Loan portfolio aging analysis
Loans receivable	118,239	56,410
Non-accrual loans with no ACL	28,961	29,532
Non-accrual loans with ACL	21,571	2,432
Financial Asset, Not Past Due
Loan portfolio aging analysis
Loans receivable	13,313,792	11,066,286
Residential Real Estate
Loan portfolio aging analysis
Loans receivable	1,051,883	802,508
Residential Real Estate | Accruing loans 30-59 days past due
Loan portfolio aging analysis
Loans receivable	2,132	6,058
Residential Real Estate | Accruing loans 60-89 days past due
Loan portfolio aging analysis
Loans receivable	457	584
Residential Real Estate | Accruing loans 90 days or more past due
Loan portfolio aging analysis
Loans receivable	223	934
Residential Real Estate | Financial Asset, Past Due
Loan portfolio aging analysis
Loans receivable	5,229	10,979
Non-accrual loans with no ACL	2,162	3,129
Non-accrual loans with ACL	255	274
Residential Real Estate | Financial Asset, Not Past Due
Loan portfolio aging analysis
Loans receivable	1,046,654	791,529
Commercial Real Estate
Loan portfolio aging analysis
Loans receivable	8,630,831	6,315,895
Commercial Real Estate | Accruing loans 30-59 days past due
Loan portfolio aging analysis
Loans receivable	26,063	3,854
Commercial Real Estate | Accruing loans 60-89 days past due
Loan portfolio aging analysis
Loans receivable	9,537	2,299
Commercial Real Estate | Accruing loans 90 days or more past due
Loan portfolio aging analysis
Loans receivable	15,345	231
Commercial Real Estate | Financial Asset, Past Due
Loan portfolio aging analysis
Loans receivable	71,433	22,201
Non-accrual loans with no ACL	20,040	14,030
Non-accrual loans with ACL	448	1,787
Commercial Real Estate | Financial Asset, Not Past Due
Loan portfolio aging analysis
Loans receivable	8,559,398	6,293,694
Other Commercial
Loan portfolio aging analysis
Loans receivable	2,664,190	3,054,817
Other Commercial | Accruing loans 30-59 days past due
Loan portfolio aging analysis
Loans receivable	5,464	4,039
Other Commercial | Accruing loans 60-89 days past due
Loan portfolio aging analysis
Loans receivable	1,652	809
Other Commercial | Accruing loans 90 days or more past due
Loan portfolio aging analysis
Loans receivable	1,383	293
Other Commercial | Financial Asset, Past Due
Loan portfolio aging analysis
Loans receivable	33,827	14,650
Non-accrual loans with no ACL	4,563	9,231
Non-accrual loans with ACL	20,765	278
Other Commercial | Financial Asset, Not Past Due
Loan portfolio aging analysis
Loans receivable	2,630,363	3,040,167
Home Equity
Loan portfolio aging analysis
Loans receivable	736,288	636,405
Home Equity | Accruing loans 30-59 days past due
Loan portfolio aging analysis
Loans receivable	1,582	2,130
Home Equity | Accruing loans 60-89 days past due
Loan portfolio aging analysis
Loans receivable	512	756
Home Equity | Accruing loans 90 days or more past due
Loan portfolio aging analysis
Loans receivable	57	135
Home Equity | Financial Asset, Past Due
Loan portfolio aging analysis
Loans receivable	3,962	5,734
Non-accrual loans with no ACL	1,712	2,664
Non-accrual loans with ACL	99	49
Home Equity | Financial Asset, Not Past Due
Loan portfolio aging analysis
Loans receivable	732,326	630,671
Other Consumer
Loan portfolio aging analysis
Loans receivable	348,839	313,071
Other Consumer | Accruing loans 30-59 days past due
Loan portfolio aging analysis
Loans receivable	2,840	1,042
Other Consumer | Accruing loans 60-89 days past due
Loan portfolio aging analysis
Loans receivable	327	1,150
Other Consumer | Accruing loans 90 days or more past due
Loan portfolio aging analysis
Loans receivable	133	132
Other Consumer | Financial Asset, Past Due
Loan portfolio aging analysis
Loans receivable	3,788	2,846
Non-accrual loans with no ACL	484	478
Non-accrual loans with ACL	4	44
Other Consumer | Financial Asset, Not Past Due
Loan portfolio aging analysis
Loans receivable	$ 345,051	$ 310,225