Income Taxes - Schedule of effective income tax rate reconciliation (Details)	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Computation of Effective Income Tax Rate [Abstract]
Federal statutory tax rate	34.00%	34.00%
State taxes	(0.90%)	1.40%
Non deductible expenses	19.40%	2.70%
Tax credits	(90.60%)	(6.70%)
Stock based compensation	(69.60%)	(0.00%)
Foreign income tax rate differential	(14.00%)	(2.10%)
Repatriation Tax	110.50%	0.00%
Impact of Tax Cuts and Jobs Act enactment	1241.00%	0.00%
Valuation allowance	0.00%	0.10%
Tax return and audit adjustments	(107.30%)	0.00%
Contingent purchase revaluation	(88.00%)	0.00%
Other	(1.70%)	2.00%
Total	1032.80%	31.40%

Effective Income Tax Rate Reconciliation, Business Acquisition, Contingent Consideration, Percent

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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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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.

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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 tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits.

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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 settlements. Including, but not limited to, domestic tax settlement, foreign tax settlement, state and local tax settlement, and other tax settlements.

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