Share-Based Compensation Plan - Activity in stock (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Additional disclosures
Compensation expense	$ 378	$ 498
Restricted Stock Awards and Units.
Restricted Stock Awards and Units
Outstanding at beginning of period	260,850	325,030
Granted	70,850	59,374
Vested	(96,618)	(81,092)
Forfeited or cancelled	(2,209)
Outstanding at end of period	232,873	303,312
Weighted Average Grant Date Fair Value
Outstanding at beginning of period	$ 21.04	$ 19.48
Granted	28.39	26.36
Vested	18.66	20.72
Forfeited or cancelled	22.75
Outstanding at end of period	$ 23.33	$ 20.49
Additional disclosures
Unrecognized compensation cost	$ 3,100
Weighted average period	2 years 10 months 24 days

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

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

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