Taxes - Reconciliation of the United States Federal Statutory Corporate Tax Rate to Company's Effective Tax Rate or Income Tax Provision (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Other Tax Expense (Benefit)	$ 1,932,000	$ 1,847,000	$ 2,502,000
Income tax expense at U.S. federal statutory corporate tax rate	21.00%	21.00%	35.00%
State income taxes, net of federal benefit	2.00%	1.00%	0.00%
Foreign tax rate differential	(9.00%)	(9.00%)	(27.00%)
Tax credit	(1.00%)	0.00%	(1.00%)
Discrete tax benefit related to employee stock options	(4.00%)	(4.00%)	(14.00%)
Discrete tax expense (benefit) related to Tax Act	0.00%	(3.00%)	36.00%
Discrete tax expense related to write-down of deferred tax assets	0.00%	0.00%	5.00%
Discrete tax expense related to migration of acquired IP	18.00%	0.00%	0.00%
Discrete tax (benefit) related to change in tax structure	(268.00%)	0.00%	0.00%
Discrete tax expense related to GILTI impact of change in tax structure	214.00%	0.00%	0.00%
Other discrete tax events	(1.00%)	0.00%	(1.00%)
Other	3.00%	1.00%	1.00%
Income tax expense	(25.00%)	7.00%	34.00%

Effective Income Tax Rate Reconciliation, Discrete Tax Expense, Percent

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Effective Income Tax Rate Reconciliation, Migration of Acquired Intellectual Property

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Effective Income Tax Rate Reconciliation, Tax Cuts and Jobs Act, Global Intangible Low Tax Income, 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 the expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, that is attributable to tax exempt income, equity in earnings (loss) of an unconsolidated subsidiary, minority interest income (expense), tax holiday, disposition of a business, disposition of an asset, repatriation of foreign earnings, repatriation of foreign earnings jobs creation act of 2004, change in enacted tax rate, prior year income taxes, change in deferred tax asset valuation allowance, and other adjustments.

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Percentage of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to excess tax benefit for share-based compensation cost.

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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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Amount of other income tax expense (benefit).

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