Income Taxes - Tax Cuts and Jobs Act (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2018	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Provisional income tax benefit			$ 2,800
Mandatory deemed repatriation of foreign earnings			3,800
Measurement period adjustment, income tax benefit		$ 700
Transition tax		600
Pre-tax loss carryforwards	$ 37,000	37,000
Operating loss carryforwards, subject to expiration	900	900
Deferred tax asset valuation allowance	(13,254)	(13,254)	(11,114)
Increase (decrease) in the valuation allowance		$ 2,100	(4,200)
Provisional liability			3,200
Undistributed earnings of foreign subsidiaries			$ 23,900
Foreign earnings repatriated	63,000
Taxes on foreign earnings repatriated	$ 1,000

Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Provisional Income Tax Expense (Benefit)

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Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Transition Tax For Accumulated Foreign Earnings, Provisional Income Tax Expense

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Tax Cuts And Jobs Act Of 2017, Measurement Adjustment, Transition Tax For Accumulated Foreign Earnings, Income Tax Expense

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Tax Cuts and Jobs Act, Measurement Period Adjustment, Income Tax Expense (Benefit)

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards that are subject to expiration dates.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Amount of foreign earnings repatriated from subsidiaries outside the country of domicile.

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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 repatriation of foreign earnings.

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