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

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Aggregate number of common shares reserved for future issuance.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Discount rate from fair value on purchase date that participants pay for shares.

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

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Number of shares issued under share-based payment arrangement.

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Share-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Weighted Average Grant Date Fair Value [Abstract]
Stock-based compensation expense	$ 84	$ 56	$ 214	$ 199
Restricted Stock [Member]
Shares [Roll Forward]
Nonvested balance at beginning of period (in shares)			29,576
Issued (in shares)			18,048
Vested (in shares)			(8,521)
Forfeited (in shares)			0
Nonvested balance at end of period (in shares)	39,103		39,103		29,576
Weighted Average Grant Date Fair Value [Abstract]
Non-vested balance at beginning of period (in dollars per share)			$ 18.46
Issued (in dollars per share)			22.35
Vested (in dollars per share)			17.50
Forfeited (in dollars per share)			0
Non-vested balance at end of period (in dollars per share)	$ 20.46		$ 20.46		$ 18.46
Weighted-average remaining vesting period for recognition			1 year 6 months 7 days
Fair value of restricted stock granted			$ 403	298
Unrecognized stock-based compensation expense	$ 411	$ 314	$ 411	$ 314
2016 Stock Incentive Plan [Member]
Stock option plan activity [Abstract]
Shares available for grant (in shares)	300,000		300,000
ESPP [Member]
Weighted Average Grant Date Fair Value [Abstract]
Discount from market price at date of purchase			5.00%		5.00%
Total stock purchases under the plan (in shares)			3,775
Shares reserved for issuance (in shares)	228,676		228,676
ESPP [Member] \| Minimum [Member]
Weighted Average Grant Date Fair Value [Abstract]
Discount from market price at date of purchase			0.00%
ESPP [Member] \| Maximum [Member]
Weighted Average Grant Date Fair Value [Abstract]
Discount from market price at date of purchase			15.00%