Income Taxes - Reconciliation of Effective Tax Rate, Percent (Details)	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Income taxes at the statutory rate	(21.00%)	(21.00%)
State taxes, net of federal benefit	(1.40%)	(1.50%)
Foreign tax rate differential	(0.40%)	11.70%
Permanent differences	9.40%	8.30%
Uncertain tax positions	(3.80%)	(2.20%)
Valuation allowance	0.80%	0.80%
Return to provision adjustments	0.10%	(5.40%)
Other	(0.00%)	(0.00%)
Effective tax rate	(16.30%)	(9.30%)

Effective Income Tax Rate Reconciliation, Return to Provision Adjustments

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage 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 changes in the valuation allowance for deferred tax assets.

+ References

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Percentage 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 applicable to statutory income tax expense (benefit) outside of the country of domicile.

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Percentage 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 applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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Percentage 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 income tax contingencies. Includes, but not limited to, domestic tax contingency, foreign tax contingency, state and local tax contingency, and other contingencies.

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