Income Taxes - Effective Income Tax (Benefit) Expense Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Statutory amount	$ (2,952)	$ 4,662	$ (733)
Valuation allowance on foreign tax credits	186	1,344	1,081
State income tax, net of federal benefit	44	792	991
Permanent differences, other	303	558	461
Permanent differences, stock compensation	(262)	328	311
Valuation allowance, other	3,108	(5,795)	(166)
Other	75	87	(77)
Income tax expense	$ 502	$ 1,976	$ 1,868
Effective income tax rate	(3.60%)	8.90%	(53.50%)
Federal statutory tax rate	21.00%	21.00%	21.00%

Effective Income Tax Rate Reconciliation, Valuation Allowance On Foreign Tax Credit

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Income Tax Reconciliation, Permanent Differences

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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Amount of reported income tax expense (benefit) in excess of (less than) expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to nondeductible expense for award under share-based payment arrangement. Includes, but is not limited to, expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax exempt income, equity in earnings (loss) of an unconsolidated subsidiary, minority noncontrolling interest income (loss), tax holiday, disposition of a business, disposition of an asset, repatriation of foreign earnings, repatriation of foreign earnings jobs creation act of 2004, increase (decrease) in enacted tax rate, prior year income taxes, increase (decrease) in deferred tax asset valuation allowance, and other adjustments.

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