Loans Receivable - Changes in the Allowance for Losses on Loans Receivable (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Changes in allowance for losses on allocated loans receivable
Beginning balance	$ 116,819	$ 125,243	$ 125,243
Current period provision	8,256	4,234
Charge-offs	(5,353)	(6,659)
Recoveries	3,087	2,079
Ending balance	122,809	124,897	116,819
Off-Balance Sheet Exposure
Changes in allowance for losses on allocated loans receivable
Beginning balance	13,949	17,123	17,123
Current period provision	(345)	(799)
Charge-offs	0	0
Recoveries	0	0
Ending balance	13,604	16,324	13,949
Personal Banking
Changes in allowance for losses on allocated loans receivable
Beginning balance	43,464	51,706	51,706
Current period provision	2,333	(3,099)
Charge-offs	(4,666)	(5,147)
Recoveries	1,220	1,208
Ending balance	42,351	44,668	43,464
Personal Banking \| Off-Balance Sheet Exposure
Changes in allowance for losses on allocated loans receivable
Beginning balance	62	67	67
Current period provision	(1)	(2)
Charge-offs	0	0
Recoveries	0	0
Ending balance	61	65	62
Personal Banking \| Residential mortgage loans
Changes in allowance for losses on allocated loans receivable
Beginning balance	14,347	18,193	18,193
Current period provision	(593)	(1,399)
Charge-offs	(588)	(162)	(845)
Recoveries	109	189
Ending balance	13,275	16,821	14,347
Personal Banking \| Residential mortgage loans \| Off-Balance Sheet Exposure
Changes in allowance for losses on allocated loans receivable
Beginning balance		2	2
Current period provision		(1)
Charge-offs		0
Recoveries		0
Ending balance		1
Personal Banking \| Home equity loans
Changes in allowance for losses on allocated loans receivable
Beginning balance	4,845	5,403	5,403
Current period provision	(150)	145
Charge-offs	(273)	(412)	(1,736)
Recoveries	202	198
Ending balance	4,624	5,334	4,845
Personal Banking \| Home equity loans \| Off-Balance Sheet Exposure
Changes in allowance for losses on allocated loans receivable
Beginning balance	62	65	65
Current period provision	(1)	(1)
Charge-offs	0	0
Recoveries	0	0
Ending balance	61	64	62
Personal Banking \| Vehicle loans
Changes in allowance for losses on allocated loans receivable
Beginning balance	22,389	26,911	26,911
Current period provision	1,815	(3,694)
Charge-offs	(2,301)	(2,588)	(8,809)
Recoveries	552	432
Ending balance	22,455	21,061	22,389
Personal Banking \| Consumer loans
Changes in allowance for losses on allocated loans receivable
Beginning balance	1,883	1,199	1,199
Current period provision	1,261	1,849
Charge-offs	(1,504)	(1,985)	(5,929)
Recoveries	357	389
Ending balance	1,997	1,452	1,883
Commercial Banking
Changes in allowance for losses on allocated loans receivable
Beginning balance	73,355	73,537	73,537
Current period provision	5,923	7,333
Charge-offs	(687)	(1,512)
Recoveries	1,867	871
Ending balance	80,458	80,229	73,355
Commercial Banking \| Off-Balance Sheet Exposure
Changes in allowance for losses on allocated loans receivable
Beginning balance	13,887	17,056	17,056
Current period provision	(344)	(797)
Charge-offs	0	0
Recoveries	0	0
Ending balance	13,543	16,259	13,887
Commercial Banking \| Commercial real estate loans
Changes in allowance for losses on allocated loans receivable
Beginning balance	44,328	51,267	51,267
Current period provision	(151)	3,073
Charge-offs	(116)	(349)	(15,321)
Recoveries	1,522	483
Ending balance	45,583	54,474	44,328
Commercial Banking \| Commercial real estate loans \| Off-Balance Sheet Exposure
Changes in allowance for losses on allocated loans receivable
Beginning balance	4,154	6,147	6,147
Current period provision	(1,198)	71
Charge-offs	0	0
Recoveries	0	0
Ending balance	2,956	6,218	4,154
Commercial Banking \| Commercial real estate loans - owner occupied
Changes in allowance for losses on allocated loans receivable
Beginning balance	3,882	3,775	3,775
Current period provision	298	272
Charge-offs	0	0	0
Recoveries	7	8
Ending balance	4,187	4,055	3,882
Commercial Banking \| Commercial real estate loans - owner occupied \| Off-Balance Sheet Exposure
Changes in allowance for losses on allocated loans receivable
Beginning balance	160	173	173
Current period provision	(24)	(19)
Charge-offs	0	0
Recoveries	0	0
Ending balance	136	154	160
Commercial Banking \| Commercial loans
Changes in allowance for losses on allocated loans receivable
Beginning balance	25,145	18,495	18,495
Current period provision	5,776	3,988
Charge-offs	(571)	(1,163)	(14,462)
Recoveries	338	380
Ending balance	30,688	21,700	25,145
Commercial Banking \| Commercial loans \| Off-Balance Sheet Exposure
Changes in allowance for losses on allocated loans receivable
Beginning balance	9,573	10,736	10,736
Current period provision	878	(849)
Charge-offs	0	0
Recoveries	0	0
Ending balance	$ 10,451	$ 9,887	$ 9,573

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

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- Definition

Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from recovery. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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- Definition

Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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- Definition

Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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