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Stock-Based Compensation Plans - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Oct. 25, 2018
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	9,300	7,550	7,400
Fair value of stock award granted (in dollars per share)	$ 48.11	$ 53.40	$ 50.55
Forfeited (in shares)	1,940		100
Forfeited (in dollars per share)	$ 49.51		$ 42.35
Share-based board compensation earned	$ 319	$ 274	$ 269
Unrecognized compensation cost	$ 880	$ 835
Expected weighted average period of compensation cost recognition (in years)	4 years 3 months 18 days	4 years 6 months
Restricted stock \| Year 1
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage (as a percent)	20.00%
Restricted stock \| Year 2
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage (as a percent)	20.00%
Restricted stock \| Year 3
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage (as a percent)	20.00%
Restricted stock \| Year 4
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage (as a percent)	20.00%
Restricted stock \| Year 5
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage (as a percent)	20.00%
2008 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued (in shares)	0	0	0
2018 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued (in shares)	9,300	7,550
Number of shares authorized (in shares)				200,000