Share-Based Compensation - Activity in stock (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Additional disclosures
Compensation expense	$ 1.9	$ 3.1	$ 1.9
Restricted Stock Awards and Units.
Restricted Stock Awards and Units
Outstanding at beginning of period	260,850	325,030
Granted	102,265	66,664
Vested	(113,562)	(104,119)
Forfeited or cancelled	(11,067)	(26,725)
Outstanding at end of period	238,486	260,850	325,030
Weighted Average Grant Date Fair Value
Outstanding at beginning of period	$ 21.04	$ 19.48
Granted	25.44	26.63
Vested	19.25	20.51
Forfeited or cancelled	23.90	18.03
Outstanding at end of period	$ 23.65	$ 21.04	$ 19.48
Additional disclosures
Unrecognized compensation cost	$ 2.5	$ 2.2
Weighted average period	2 years 8 months 12 days	2 years 10 months 24 days
Restricted stock awards
Restricted Stock Awards and Units
Outstanding at beginning of period	140,228
Outstanding at end of period	128,267	140,228
Restricted stock units
Restricted Stock Awards and Units
Outstanding at beginning of period	120,622
Outstanding at end of period	110,219	120,622

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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

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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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The weighted average fair value at grant date for nonvested equity-based awards issued 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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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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