The aggregate unrecognized cost of equity-based awards expected to be recognized in the future.

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Employee service share based compensation nonvested awards total compensation cost not yet recognized next twelve months.

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The number of anniversary dates.

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Percentage of restricted stock units granted as result of meeting growth rates.

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Share-based Compensation Arrangement by Share-based Payment Award incentive stock options outstanding number.

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The number of shares (or other type of equity) which are non-qualified options to purchase under the plan.

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Share based compensation arrangement by share based payment award restricted stock options to purchase number of shares.

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Amount of cost to be recognized for option under share-based payment arrangement, due in the fifth fiscal year following the latest fiscal year.

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Amount of cost to be recognized for option under share-based payment arrangement, due in the fourth fiscal year following the latest fiscal year.

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Amount of cost to be recognized for option under share-based payment arrangement, due in the second fiscal year following the latest fiscal year.

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Amount of cost to be recognized for option under share-based payment arrangement, due in the third fiscal year following the latest fiscal year.

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

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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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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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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.

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Number of shares authorized for issuance under share-based payment arrangement.

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

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Percentage of vesting of award under share-based payment arrangement.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Share-Based Payment Arrangements (Narrative) (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($) item $ / shares shares	Dec. 31, 2020 USD ($) shares	Dec. 31, 2019 $ / shares	Dec. 31, 2018 $ / shares	Dec. 31, 2017 $ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, Granted \| shares	0	0
Long Term Incentive Plan 2005 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of incentive stock options outstanding \| shares	0
Share-based compensation arrangement by share-based payment award, non-qualified stock options to purchase number of shares \| shares	14,157
Long Term Incentive Plan 2015 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of incentive stock options outstanding \| shares	0
Share-based compensation arrangement by share-based payment award, number of shares authorized \| shares	2,000,000
Share-based compensation arrangement by share-based payment award, restricted stock options to purchase number of shares \| shares	872,532
Long Term Incentive Plan 2005 and 2015 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to non-vested share-based compensation arrangements	$ 0
Non Qualified Stock Options [Member] \| Long Term Incentive Plan 2005 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award vesting rights, percentage	100.00%
Stock-based compensation incentive stock options grant under incentive plan termination period	10 years
Share-based payment, award vesting period	6 months
Non Qualified Stock Options [Member] \| Long Term Incentive Plan 2005 [Member] \| First Seven Anniversary Dates [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of anniversary dates \| item	7
Non Qualified Stock Options [Member] \| Long Term Incentive Plan 2005 [Member] \| Two Hundred Thousand Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options vested or expected to vest \| shares	200,000
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to non-vested share-based compensation arrangements	$ 2,300
Allocated share-based compensation expense (benefit)	228	$ (400)
Income tax benefit (expense) of share-based payments recognized in income	48	$ (84)
Employee Service Share-based Compensation Nonvested Awards, Total Compensation Cost Expected to Recognized	1,500
2022	600
2023	500
2024	300
2025	100
2026	$ 14
Restricted Stock Units (RSUs) [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of restricted stock units granted as result of meeting growth rates	50.00%
Restricted Stock Units (RSUs) [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of restricted stock units granted as result of meeting growth rates	150.00%
Restricted Stock Units (RSUs) [Member] \| Long Term Incentive Plan 2015 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Other than options, grant date fair value \| $ / shares	$ 4.21		$ 18.10	$ 10.87	$ 10.20
Restricted Stock Units (RSUs) [Member] \| Long Term Incentive Plan 2015 [Member] \| Third Anniversary [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award vesting rights, percentage	50.00%
Restricted Stock Units (RSUs) [Member] \| Long Term Incentive Plan 2015 [Member] \| Fourth Anniversary [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award vesting rights, percentage	80.00%
Restricted Stock Units (RSUs) [Member] \| Long Term Incentive Plan 2015 [Member] \| Fifth Anniversary [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award vesting rights, percentage	100.00%