Income Taxes (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Jan. 01, 2019	Jan. 01, 2018	Jan. 01, 2017
Tax Credit Carryforward [Line Items]
General business credit	$ 9
Foreign tax credit carry-forwards	2,345	$ 2,360
Cumulative effect adjustment				$ 1,680	$ (2,748)
Non-current deferred income tax asset	45	226
Valuation allowance, deferred tax asset	308
Interest and penalities	11	16
Non-current income taxes payable	147	136
Reasonably possible decrease in unrecognized tax benefit	32
Reduction to deferred tax assets and corresponding valuation allowance related to 2017 Tax Act	484	$ 484	$ 1,780
Net tax benefit related to estimate of the provisions of the 2017 Tax Act			$ 54
Reduction to deferred tax assets and corresponding valuation allowance related to 2017 Tax Act	2,264
Net tax benefit related to 2017 Tax Act	54
Transitional toll tax related to 2017 Tax Act	1,209
Accounting Standards Update 2016-09 | Deferred Tax Assets, Tax Credit Carryforwards And Operating Loss Carryforwards
Tax Credit Carryforward [Line Items]
Cumulative effect adjustment						$ 1,117
Difference between Revenue Guidance in Effect before and after Topic 606 | Accounting Standards Update 2014-09
Tax Credit Carryforward [Line Items]
Non-current deferred income tax asset					$ 202
State and Local Jurisdiction
Tax Credit Carryforward [Line Items]
Unrecognized excess tax benefit	138
Research Tax Credit Carryforward | Internal Revenue Service (IRS)
Tax Credit Carryforward [Line Items]
Unrecognized excess tax benefit	5,234
Research Tax Credit Carryforward | State and Local Jurisdiction
Tax Credit Carryforward [Line Items]
Unrecognized excess tax benefit	$ 3,844