Share-Based Compensation Plan - Activity in stock (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Restricted Stock Awards and Units.
Restricted Stock Awards and Units
Outstanding at beginning of period	238,486	260,850
Granted	117,706	102,265
Vested	(98,138)	(113,562)
Forfeited or cancelled	(26,397)	(11,067)
Outstanding at end of period	231,657	238,486
Weighted Average Grant Date Fair Value
Outstanding at beginning of period	$ 23.65	$ 21.04
Granted	19.95	25.44
Vested	21.44	19.25
Forfeited or cancelled	21.33	23.90
Outstanding at end of period	$ 22.96	$ 23.65
Additional disclosures
Unrecognized compensation cost	$ 2.7	$ 2.5
Weighted average period	2 years 3 months 18 days	2 years 8 months 12 days
Restricted stock awards
Restricted Stock Awards and Units
Outstanding at beginning of period	128,267
Outstanding at end of period	120,497	128,267
Restricted stock units
Restricted Stock Awards and Units
Outstanding at beginning of period	110,219
Outstanding at end of period	111,160	110,219

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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