Loans Receivable - Loans Modified with Payment Default (Details) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2026	Jun. 30, 2025
Term extension
Financing Receivable, Modified, Subsequent Default [Line Items]
Loans with payment default and modified	$ 183	$ 10
Payment delay
Financing Receivable, Modified, Subsequent Default [Line Items]
Loans with payment default and modified	8,149	1,901
Personal Banking \| Term extension
Financing Receivable, Modified, Subsequent Default [Line Items]
Loans with payment default and modified	183	10
Personal Banking \| Term extension \| Residential mortgage loans
Financing Receivable, Modified, Subsequent Default [Line Items]
Loans with payment default and modified	183	0
Personal Banking \| Term extension \| Home equity loans
Financing Receivable, Modified, Subsequent Default [Line Items]
Loans with payment default and modified	0	10
Personal Banking \| Payment delay
Financing Receivable, Modified, Subsequent Default [Line Items]
Loans with payment default and modified	0	183
Personal Banking \| Payment delay \| Residential mortgage loans
Financing Receivable, Modified, Subsequent Default [Line Items]
Loans with payment default and modified	0	183
Personal Banking \| Payment delay \| Home equity loans
Financing Receivable, Modified, Subsequent Default [Line Items]
Loans with payment default and modified	0	0
Commercial Banking \| Term extension
Financing Receivable, Modified, Subsequent Default [Line Items]
Loans with payment default and modified	0	0
Commercial Banking \| Term extension \| Commercial real estate loans
Financing Receivable, Modified, Subsequent Default [Line Items]
Loans with payment default and modified	0	0
Commercial Banking \| Term extension \| Commercial and industrial loans
Financing Receivable, Modified, Subsequent Default [Line Items]
Loans with payment default and modified	0	0
Commercial Banking \| Payment delay
Financing Receivable, Modified, Subsequent Default [Line Items]
Loans with payment default and modified	8,149	1,718
Commercial Banking \| Payment delay \| Commercial real estate loans
Financing Receivable, Modified, Subsequent Default [Line Items]
Loans with payment default and modified	8,102	0
Commercial Banking \| Payment delay \| Commercial and industrial loans
Financing Receivable, Modified, Subsequent Default [Line Items]
Loans with payment default and modified	$ 47	$ 1,718