Loans Receivable - Financing Receivable Weighted Average Modified Period (Details)	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Troubled debt restructurings
Weighted-average interest rate reduction	4.00%	3.00%	4.00%	2.00%
Weighted-average term extension in months	11 months	13 months	11 months	13 months
Weighted-average payment deferral in years		6 months	6 months	6 months
Personal Banking
Troubled debt restructurings
Weighted-average interest rate reduction	0.00%	0.00%	1.00%	0.00%
Weighted-average term extension in months	168 months	141 months	122 months	134 months
Weighted-average payment deferral in years		0 years	0 years	0 years
Personal Banking \| Residential mortgage loans
Troubled debt restructurings
Weighted-average interest rate reduction	0.00%	0.00%	1.00%	0.00%
Weighted-average term extension in months	160 months	161 months	121 months	147 months
Weighted-average payment deferral in years		0 years	0 years	0 years
Personal Banking \| Home equity loans
Troubled debt restructurings
Weighted-average interest rate reduction	0.00%	0.00%	0.00%	0.00%
Weighted-average term extension in months	222 months	67 months	144 months	87 months
Weighted-average payment deferral in years		0 years	0 years	0 years
Commercial Banking
Troubled debt restructurings
Weighted-average interest rate reduction	4.00%	3.00%	5.00%	2.00%
Weighted-average term extension in months	10 months	12 months	9 months	12 months
Weighted-average payment deferral in years		6 months	6 months	6 months
Commercial Banking \| Commercial real estate loans
Troubled debt restructurings
Weighted-average interest rate reduction	2.00%	0.00%	2.00%	0.00%
Weighted-average term extension in months	8 months	12 months	9 months	12 months
Weighted-average payment deferral in years		6 months	6 months	6 months
Commercial Banking \| Commercial real estate loans - owner occupied
Troubled debt restructurings
Weighted-average interest rate reduction			4.00%	0.00%
Weighted-average term extension in months			17 months	6 months
Weighted-average payment deferral in years			0 years	0 years
Commercial Banking \| Commercial and industrial loans
Troubled debt restructurings
Weighted-average interest rate reduction	8.00%	3.00%	5.00%	3.00%
Weighted-average term extension in months	12 months	74 months	9 months	73 months
Weighted-average payment deferral in years		3 months 18 days	6 months	9 months

Financing Receivable, Modified, Weighted Average Payment Deferral, Period

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 12A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481933/310-10-55-12A

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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(2)
-Publisher FASB
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-42

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- Definition

Percentage of decrease in weighted-average contractual interest rate of financing receivable modified for debtor experiencing financial difficulty.

+ References

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- Definition

Period of increase in weighted-average maturity of financing receivable modified for debtor experiencing financial difficulty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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