Loans Receivable - Financing Receivable Weighted Average Modified Period (Details)	3 Months Ended	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Troubled debt restructurings
Weighted-average interest rate reduction	2.00%		2.00%	12.00%
Weighted-average term extension in months	0 months	66 months	118 months	45 months
Weighted-average payment deferral in years	1 year		1 year
Personal Banking
Troubled debt restructurings
Weighted-average interest rate reduction	0.00%		2.00%	12.00%
Weighted-average term extension in months	112 months	66 months	119 months	111 months
Weighted-average payment deferral in years	0 years		0 years
Personal Banking \| Residential mortgage loans
Troubled debt restructurings
Weighted-average interest rate reduction	0.00%		0.00%	0.00%
Weighted-average term extension in months	220 months	100 months	145 months	132 months
Weighted-average payment deferral in years	0 years		0 years
Personal Banking \| Home equity loans
Troubled debt restructurings
Weighted-average interest rate reduction	0.00%		2.00%	0.00%
Weighted-average term extension in months	73 months	42 months	97 months	73 months
Weighted-average payment deferral in years	0 years		0 years
Personal Banking \| Consumer loans
Troubled debt restructurings
Weighted-average interest rate reduction	0.00%		12.00%	12.00%
Weighted-average term extension in months	0 months	9 months	356 months	319 months
Weighted-average payment deferral in years	0 years		0 years
Commercial Banking
Troubled debt restructurings
Weighted-average interest rate reduction	2.00%		2.00%	0.00%
Weighted-average term extension in months	0 months	0 months	117 months	13 months
Weighted-average payment deferral in years	1 year		1 year
Commercial Banking \| Commercial real estate loans - owner occupied
Troubled debt restructurings
Weighted-average interest rate reduction	2.00%		2.00%	0.00%
Weighted-average term extension in months	0 months	0 months	0 months	0 months
Weighted-average payment deferral in years	0 years		0 years
Commercial Banking \| Commercial real estate loans
Troubled debt restructurings
Weighted-average interest rate reduction			0.00%	0.00%
Weighted-average term extension in months			117 months	25 months
Weighted-average payment deferral in years	1 year		1 year
Commercial Banking \| Commercial loans
Troubled debt restructurings
Weighted-average interest rate reduction			4.00%	0.00%
Weighted-average term extension in months			118 months	9 months
Weighted-average payment deferral in years	0 years		0 years

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