Aggregate percentage of stock based awards to me matured.

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- Definition

Number of nonqualified options or restricted stock for key employees and independent director.

+ References

No definition available.

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- Definition

Starting period of vesting of share based award.

+ References

No definition available.

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- Definition

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

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-Publisher FASB
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- Definition

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

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- Definition

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

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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- Definition

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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- Definition

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

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

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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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Stock-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of nonqualified options or restricted stock for key employees and independent director (in shares)	507,671
Granted (in shares)	25,466
Weighted-average grant date fair value (in dollars per share)	$ 28.64
Vested (in shares)	27,530
Number of authorized stock-based awards available for grant (in shares)	457,448
Key Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Starting period of vesting of stock based award	1 year
Aggregate percentage of stock based awards to be matured	100.00%
Independent Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Starting period of vesting of stock based award	1 year
Aggregate percentage of stock based awards to be matured	100.00%
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	36,968	40,978	40,108
Compensation expense	$ 1,410	$ 1,346	$ 1,545
Unrecognized compensation cost related to nonvested restricted stock	1,055	1,026
Fair value of shares vesting during period	1,123	1,462	1,535
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Income tax benefit from share-based compensation	296	283	324
Performance Based Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	384	221	$ 314
Unrecognized compensation cost related to nonvested restricted stock		$ 539
Fair value of shares vesting during period	$ 233
Vested (in shares)	7,109
Performance Based Restricted Stock Awards \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Shares, granted (in shares)	18,100	16,681	15,657
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	11,502
Weighted-average grant date fair value (in dollars per share)	$ 29.56