Loans Receivable - Changes in the Allowance for Losses on Loans Receivable (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Changes in allowance for losses on allocated loans receivable
Beginning balance	$ 124,897	$ 121,257	$ 125,243	$ 118,036	$ 118,036
Current period provision	2,169	6,010	6,403	10,880
Charge-offs	(4,869)	(5,244)	(11,528)	(9,871)
Recoveries	2,873	2,400	4,952	4,952
Ending balance	125,070	124,423	125,070	124,423	125,243
ASU 2022-02 Adoption
Changes in allowance for losses on allocated loans receivable
Beginning balance				426	426
Off-Balance Sheet Exposure
Changes in allowance for losses on allocated loans receivable
Beginning balance	16,324	13,039	17,123	12,913	12,913
Current period provision	(2,539)	2,920	(3,338)	3,046
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	13,785	15,959	13,785	15,959	17,123
Off-Balance Sheet Exposure | ASU 2022-02 Adoption
Changes in allowance for losses on allocated loans receivable
Beginning balance				0	0
Personal Banking
Changes in allowance for losses on allocated loans receivable
Beginning balance	44,668	51,617	51,706	48,887	48,887
Current period provision	(453)	1,129	(3,552)	5,727
Charge-offs	(3,050)	(3,552)	(8,197)	(6,657)
Recoveries	2,076	1,657	3,284	2,894
Ending balance	43,241	50,851	43,241	50,851	51,706
Personal Banking | ASU 2022-02 Adoption
Changes in allowance for losses on allocated loans receivable
Beginning balance				0	0
Personal Banking | Off-Balance Sheet Exposure
Changes in allowance for losses on allocated loans receivable
Beginning balance	65	63	67	78	78
Current period provision	(1)	5	(3)	(10)
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	64	68	64	68	67
Personal Banking | Off-Balance Sheet Exposure | ASU 2022-02 Adoption
Changes in allowance for losses on allocated loans receivable
Beginning balance				0	0
Personal Banking | Residential mortgage loans
Changes in allowance for losses on allocated loans receivable
Beginning balance	16,821	19,238	18,193	19,261	19,261
Current period provision	(2,375)	(1,676)	(3,774)	(1,677)
Charge-offs	(252)	(545)	(414)	(752)	(1,189)
Recoveries	805	539	994	724
Ending balance	14,999	17,556	14,999	17,556	18,193
Personal Banking | Residential mortgage loans | ASU 2022-02 Adoption
Changes in allowance for losses on allocated loans receivable
Beginning balance				0	0
Personal Banking | Residential mortgage loans | Off-Balance Sheet Exposure
Changes in allowance for losses on allocated loans receivable
Beginning balance	1	3	2	4	4
Current period provision	0	1	(1)	0
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	1	4	1	4	2
Personal Banking | Residential mortgage loans | Off-Balance Sheet Exposure | ASU 2022-02 Adoption
Changes in allowance for losses on allocated loans receivable
Beginning balance				0	0
Personal Banking | Home equity loans
Changes in allowance for losses on allocated loans receivable
Beginning balance	5,334	5,481	5,403	5,902	5,902
Current period provision	(279)	(456)	(134)	(906)
Charge-offs	(237)	(235)	(649)	(399)	(852)
Recoveries	392	212	590	405
Ending balance	5,210	5,002	5,210	5,002	5,403
Personal Banking | Home equity loans | ASU 2022-02 Adoption
Changes in allowance for losses on allocated loans receivable
Beginning balance				0	0
Personal Banking | Home equity loans | Off-Balance Sheet Exposure
Changes in allowance for losses on allocated loans receivable
Beginning balance	64	60	65	74	74
Current period provision	(1)	4	(2)	(10)
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	63	64	63	64	65
Personal Banking | Home equity loans | Off-Balance Sheet Exposure | ASU 2022-02 Adoption
Changes in allowance for losses on allocated loans receivable
Beginning balance				0	0
Personal Banking | Vehicle loans
Changes in allowance for losses on allocated loans receivable
Beginning balance	21,061	26,166	26,911	23,059	23,059
Current period provision	1,767	2,030	(1,927)	6,283
Charge-offs	(1,926)	(1,539)	(4,514)	(3,207)	(6,468)
Recoveries	462	626	894	1,148
Ending balance	21,364	27,283	21,364	27,283	26,911
Personal Banking | Vehicle loans | ASU 2022-02 Adoption
Changes in allowance for losses on allocated loans receivable
Beginning balance				0	0
Personal Banking | Consumer loans
Changes in allowance for losses on allocated loans receivable
Beginning balance	1,452	732	1,199	665	665
Current period provision	434	1,231	2,283	2,027
Charge-offs	(635)	(1,233)	(2,620)	(2,299)	(5,983)
Recoveries	417	280	806	617
Ending balance	1,668	1,010	1,668	1,010	1,199
Personal Banking | Consumer loans | ASU 2022-02 Adoption
Changes in allowance for losses on allocated loans receivable
Beginning balance				0	0
Commercial Banking
Changes in allowance for losses on allocated loans receivable
Beginning balance	80,229	69,640	73,537	69,149	69,149
Current period provision	2,622	4,881	9,955	5,153
Charge-offs	(1,819)	(1,692)	(3,331)	(3,214)
Recoveries	797	743	1,668	2,058
Ending balance	81,829	73,572	81,829	73,572	73,537
Commercial Banking | ASU 2022-02 Adoption
Changes in allowance for losses on allocated loans receivable
Beginning balance				426	426
Commercial Banking | Off-Balance Sheet Exposure
Changes in allowance for losses on allocated loans receivable
Beginning balance	16,259	12,976	17,056	12,835	12,835
Current period provision	(2,538)	2,915	(3,335)	3,056
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	13,721	15,891	13,721	15,891	17,056
Commercial Banking | Off-Balance Sheet Exposure | ASU 2022-02 Adoption
Changes in allowance for losses on allocated loans receivable
Beginning balance				0	0
Commercial Banking | Commercial real estate loans
Changes in allowance for losses on allocated loans receivable
Beginning balance	54,474	45,404	51,267	44,506	44,506
Current period provision	(3,785)	4,576	(712)	4,697
Charge-offs	(500)	(415)	(849)	(1,072)	(2,298)
Recoveries	370	491	853	1,499
Ending balance	50,559	50,056	50,559	50,056	51,267
Commercial Banking | Commercial real estate loans | ASU 2022-02 Adoption
Changes in allowance for losses on allocated loans receivable
Beginning balance				426	426
Commercial Banking | Commercial real estate loans | Off-Balance Sheet Exposure
Changes in allowance for losses on allocated loans receivable
Beginning balance	6,218	5,924	6,147	5,375	5,375
Current period provision	(1,768)	1,731	(1,697)	2,280
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	4,450	7,655	4,450	7,655	6,147
Commercial Banking | Commercial real estate loans | Off-Balance Sheet Exposure | ASU 2022-02 Adoption
Changes in allowance for losses on allocated loans receivable
Beginning balance				0	0
Commercial Banking | Commercial real estate loans - owner occupied
Changes in allowance for losses on allocated loans receivable
Beginning balance	4,055	3,351	3,775	4,004	4,004
Current period provision	(453)	189	(181)	(485)
Charge-offs	0	(68)	0	(68)	(68)
Recoveries	13	26	21	47
Ending balance	3,615	3,498	3,615	3,498	3,775
Commercial Banking | Commercial real estate loans - owner occupied | ASU 2022-02 Adoption
Changes in allowance for losses on allocated loans receivable
Beginning balance				0	0
Commercial Banking | Commercial real estate loans - owner occupied | Off-Balance Sheet Exposure
Changes in allowance for losses on allocated loans receivable
Beginning balance	154	441	173	379	379
Current period provision	(3)	(121)	(22)	(59)
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	151	320	151	320	173
Commercial Banking | Commercial real estate loans - owner occupied | Off-Balance Sheet Exposure | ASU 2022-02 Adoption
Changes in allowance for losses on allocated loans receivable
Beginning balance				0	0
Commercial Banking | Commercial loans
Changes in allowance for losses on allocated loans receivable
Beginning balance	21,700	20,885	18,495	20,639	20,639
Current period provision	6,860	116	10,848	941
Charge-offs	(1,319)	(1,209)	(2,482)	(2,074)	(4,166)
Recoveries	414	226	794	512
Ending balance	27,655	20,018	27,655	20,018	18,495
Commercial Banking | Commercial loans | ASU 2022-02 Adoption
Changes in allowance for losses on allocated loans receivable
Beginning balance				0	0
Commercial Banking | Commercial loans | Off-Balance Sheet Exposure
Changes in allowance for losses on allocated loans receivable
Beginning balance	9,887	6,611	10,736	7,081	7,081
Current period provision	(767)	1,305	(1,616)	835
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	$ 9,120	$ 7,916	$ 9,120	7,916	10,736
Commercial Banking | Commercial loans | Off-Balance Sheet Exposure | ASU 2022-02 Adoption
Changes in allowance for losses on allocated loans receivable
Beginning balance				$ 0	$ 0