Loans Receivable - Amortized Cost Basis of Loans Modified (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Troubled debt restructurings
Total class of financing receivable	0.01%	0.00%	0.28%	0.01%
Committed to lend additional amounts	$ 41	$ 31	$ 41	$ 31
Payment delay
Troubled debt restructurings
Loans modified in period			29,764
Term extension
Troubled debt restructurings
Loans modified in period	57	$ 200	1,289	1,308
Interest rate reduction
Troubled debt restructurings
Loans modified in period	$ 697		697
Combination term extension and interest rate reduction
Troubled debt restructurings
Loans modified in period			$ 95	$ 3
Personal Banking
Troubled debt restructurings
Total class of financing receivable	0.00%	0.00%	0.02%	0.01%
Personal Banking | Payment delay
Troubled debt restructurings
Loans modified in period			$ 0
Personal Banking | Term extension
Troubled debt restructurings
Loans modified in period	$ 57	$ 200	1,048	$ 428
Personal Banking | Interest rate reduction
Troubled debt restructurings
Loans modified in period	$ 0		0
Personal Banking | Combination term extension and interest rate reduction
Troubled debt restructurings
Loans modified in period			$ 86	$ 3
Personal Banking | Residential mortgage loans
Troubled debt restructurings
Total class of financing receivable	0.00%	0.00%	0.01%	0.01%
Personal Banking | Residential mortgage loans | Payment delay
Troubled debt restructurings
Loans modified in period			$ 0
Personal Banking | Residential mortgage loans | Term extension
Troubled debt restructurings
Loans modified in period	$ 15	$ 82	497	$ 262
Personal Banking | Residential mortgage loans | Interest rate reduction
Troubled debt restructurings
Loans modified in period	$ 0		0
Personal Banking | Residential mortgage loans | Combination term extension and interest rate reduction
Troubled debt restructurings
Loans modified in period			$ 0	$ 0
Personal Banking | Home equity loans
Troubled debt restructurings
Total class of financing receivable	0.00%	0.01%	0.05%	0.01%
Personal Banking | Home equity loans | Payment delay
Troubled debt restructurings
Loans modified in period			$ 0
Personal Banking | Home equity loans | Term extension
Troubled debt restructurings
Loans modified in period	$ 42	$ 118	551	$ 166
Personal Banking | Home equity loans | Interest rate reduction
Troubled debt restructurings
Loans modified in period	$ 0		0
Personal Banking | Home equity loans | Combination term extension and interest rate reduction
Troubled debt restructurings
Loans modified in period			$ 84	$ 0
Personal Banking | Consumer loans
Troubled debt restructurings
Total class of financing receivable			0.00%	0.00%
Personal Banking | Consumer loans | Payment delay
Troubled debt restructurings
Loans modified in period			$ 0
Personal Banking | Consumer loans | Term extension
Troubled debt restructurings
Loans modified in period			0	$ 0
Personal Banking | Consumer loans | Interest rate reduction
Troubled debt restructurings
Loans modified in period			0
Personal Banking | Consumer loans | Combination term extension and interest rate reduction
Troubled debt restructurings
Loans modified in period			$ 2	$ 3
Commercial Banking
Troubled debt restructurings
Total class of financing receivable	0.01%	0.00%	0.64%	0.02%
Commercial Banking | Payment delay
Troubled debt restructurings
Loans modified in period			$ 29,764
Commercial Banking | Term extension
Troubled debt restructurings
Loans modified in period	$ 0	$ 0	241	$ 880
Commercial Banking | Interest rate reduction
Troubled debt restructurings
Loans modified in period	$ 697		697
Commercial Banking | Combination term extension and interest rate reduction
Troubled debt restructurings
Loans modified in period			$ 9	$ 0
Commercial Banking | Commercial real estate loans
Troubled debt restructurings
Total class of financing receivable			1.12%	0.01%
Commercial Banking | Commercial real estate loans | Payment delay
Troubled debt restructurings
Loans modified in period			$ 29,764
Commercial Banking | Commercial real estate loans | Term extension
Troubled debt restructurings
Loans modified in period			210	$ 220
Commercial Banking | Commercial real estate loans | Interest rate reduction
Troubled debt restructurings
Loans modified in period			0
Commercial Banking | Commercial real estate loans | Combination term extension and interest rate reduction
Troubled debt restructurings
Loans modified in period			$ 0	$ 0
Commercial Banking | Commercial real estate loans - owner occupied
Troubled debt restructurings
Total class of financing receivable	0.19%	0.00%	0.19%	0.00%
Commercial Banking | Commercial real estate loans - owner occupied | Payment delay
Troubled debt restructurings
Loans modified in period			$ 0
Commercial Banking | Commercial real estate loans - owner occupied | Term extension
Troubled debt restructurings
Loans modified in period	$ 0	$ 0	0	$ 0
Commercial Banking | Commercial real estate loans - owner occupied | Interest rate reduction
Troubled debt restructurings
Loans modified in period	$ 697		697
Commercial Banking | Commercial real estate loans - owner occupied | Combination term extension and interest rate reduction
Troubled debt restructurings
Loans modified in period			$ 0	$ 0
Commercial Banking | Commercial loans
Troubled debt restructurings
Total class of financing receivable			0.00%	0.05%
Commercial Banking | Commercial loans | Payment delay
Troubled debt restructurings
Loans modified in period			$ 0
Commercial Banking | Commercial loans | Term extension
Troubled debt restructurings
Loans modified in period			31	$ 660
Commercial Banking | Commercial loans | Interest rate reduction
Troubled debt restructurings
Loans modified in period			0
Commercial Banking | Commercial loans | Combination term extension and interest rate reduction
Troubled debt restructurings
Loans modified in period			$ 9	$ 0