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, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Changes in allowance for losses on allocated loans receivable
Beginning balance	$ 150,045	$ 122,809	$ 150,212	$ 116,819	$ 116,819
Current period provision	4,280	11,456	9,234	19,712
Charge-offs	(6,803)	(7,907)	(14,035)	(13,260)
Recoveries	1,799	2,801	3,910	5,888
Ending balance	149,321	129,159	149,321	129,159	150,212
Off-Balance Sheet Exposure
Changes in allowance for losses on allocated loans receivable
Beginning balance	12,099	13,604	12,684	13,949	13,949
Current period provision	2,357	(2,712)	1,772	(3,057)
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	14,456	10,892	14,456	10,892	12,684
Personal Banking
Changes in allowance for losses on allocated loans receivable
Beginning balance	47,603	42,351	47,457	43,464	43,464
Current period provision	1,404	169	6,159	2,502
Charge-offs	(4,969)	(4,017)	(10,792)	(8,683)
Recoveries	1,385	1,302	2,599	2,522
Ending balance	45,423	39,805	45,423	39,805	47,457
Personal Banking \| Off-Balance Sheet Exposure
Changes in allowance for losses on allocated loans receivable
Beginning balance	86	61	91	62	62
Current period provision	(5)	4	(10)	3
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	81	65	81	65	91
Personal Banking \| Residential mortgage loans
Changes in allowance for losses on allocated loans receivable
Beginning balance	9,895	13,275	10,546	14,347	14,347
Current period provision	566	(1,079)	786	(1,672)
Charge-offs	(465)	(273)	(1,466)	(861)	(1,226)
Recoveries	178	166	308	275
Ending balance	10,174	12,089	10,174	12,089	10,546
Personal Banking \| Residential mortgage loans \| Off-Balance Sheet Exposure
Changes in allowance for losses on allocated loans receivable
Beginning balance	0		0
Current period provision	1		1
Charge-offs	0
Recoveries	0
Ending balance	1		1		0
Personal Banking \| Home equity loans
Changes in allowance for losses on allocated loans receivable
Beginning balance	6,340	4,624	6,149	4,845	4,845
Current period provision	35	(228)	369	(378)
Charge-offs	(383)	(413)	(674)	(686)	(1,580)
Recoveries	219	233	367	435
Ending balance	6,211	4,216	6,211	4,216	6,149
Personal Banking \| Home equity loans \| Off-Balance Sheet Exposure
Changes in allowance for losses on allocated loans receivable
Beginning balance	86	61	91	62	62
Current period provision	(6)	4	(11)	3
Charge-offs	0	0		0
Recoveries	0	0		0
Ending balance	80	65	80	65	91
Personal Banking \| Vehicle loans
Changes in allowance for losses on allocated loans receivable
Beginning balance	26,346	22,455	25,945	22,389	22,389
Current period provision	232	448	3,036	2,263
Charge-offs	(2,426)	(2,150)	(5,356)	(4,451)	(8,828)
Recoveries	592	481	1,119	1,033
Ending balance	24,744	21,234	24,744	21,234	25,945
Personal Banking \| Consumer loans
Changes in allowance for losses on allocated loans receivable
Beginning balance	5,022	1,997	4,817	1,883	1,883
Current period provision	571	1,028	1,968	2,289
Charge-offs	(1,695)	(1,181)	(3,296)	(2,685)	(6,441)
Recoveries	396	422	805	779
Ending balance	4,294	2,266	4,294	2,266	4,817
Commercial Banking
Changes in allowance for losses on allocated loans receivable
Beginning balance	102,442	80,458	102,755	73,355	73,355
Current period provision	2,876	11,287	3,075	17,210
Charge-offs	(1,834)	(3,890)	(3,243)	(4,577)
Recoveries	414	1,499	1,311	3,366
Ending balance	103,898	89,354	103,898	89,354	102,755
Commercial Banking \| Off-Balance Sheet Exposure
Changes in allowance for losses on allocated loans receivable
Beginning balance	12,013	13,543	12,593	13,887	13,887
Current period provision	2,362	(2,716)	1,782	(3,060)
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	14,375	10,827	14,375	10,827	12,593
Commercial Banking \| Commercial real estate loans
Changes in allowance for losses on allocated loans receivable
Beginning balance	56,604	45,583	58,234	44,328	44,328
Current period provision	(1,790)	7,432	(3,798)	7,281
Charge-offs	(889)	(293)	(1,143)	(409)	(14,150)
Recoveries	166	902	798	2,424
Ending balance	54,091	53,624	54,091	53,624	58,234
Commercial Banking \| Commercial real estate loans \| Off-Balance Sheet Exposure
Changes in allowance for losses on allocated loans receivable
Beginning balance	1,728	2,956	1,926	4,154	4,154
Current period provision	464	(1,059)	266	(2,257)
Charge-offs	0	0		0
Recoveries	0	0		0
Ending balance	2,192	1,897	2,192	1,897	1,926
Commercial Banking \| Commercial real estate loans - owner occupied
Changes in allowance for losses on allocated loans receivable
Beginning balance	5,030	4,187	4,679	3,882	3,882
Current period provision	(16)	(130)	332	168
Charge-offs	0	0	0	0	(336)
Recoveries	2	73	5	80
Ending balance	5,016	4,130	5,016	4,130	4,679
Commercial Banking \| Commercial real estate loans - owner occupied \| Off-Balance Sheet Exposure
Changes in allowance for losses on allocated loans receivable
Beginning balance	136	136	165	160	160
Current period provision	332	124	303	100
Charge-offs	0	0		0
Recoveries	0	0		0
Ending balance	468	260	468	260	165
Commercial Banking \| Commercial and industrial loans
Changes in allowance for losses on allocated loans receivable
Beginning balance	40,808	30,688	39,842	25,145	25,145
Current period provision	4,682	3,985	6,541	9,761
Charge-offs	(945)	(3,597)	(2,100)	(4,168)	(7,095)
Recoveries	246	524	508	862
Ending balance	44,791	31,600	44,791	31,600	39,842
Commercial Banking \| Commercial and industrial loans \| Off-Balance Sheet Exposure
Changes in allowance for losses on allocated loans receivable
Beginning balance	10,149	10,451	10,502	9,573	9,573
Current period provision	1,566	(1,781)	1,213	(903)
Charge-offs	0	0		0
Recoveries	0	0		0
Ending balance	$ 11,715	$ 8,670	$ 11,715	$ 8,670	$ 10,502

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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/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S45
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-Topic 326
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-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
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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
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-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
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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
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