Income Taxes - Income Tax Expense (Benefit), Continuing Operations, Income Tax Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Expense (Benefit), Continuing Operations, Income Tax Reconciliation [Abstract]
United States federal corporate income tax rate	34.00%
Increase (decrease) in income taxes resulting from:
Computed “expected” tax expense	$ (670)	$ 906	$ 451
State income tax expense, net of federal benefit	(156)	(37)	(31)
State research and development, investment credits	(363)	(317)	(365)
Non-deductible meals & entertainment	49	33	37
Non-deductible stock compensation expense	216	181	29
Non-deductible transaction costs	116	260	87
Non-deductible transaction costs	0	0	73
Subpart F income, net of foreign tax credits	523	61	296
Manufacturing deduction	0	(102)	(123)
Nontaxable interest income	(162)	(106)	(105)
Foreign tax rate differential	(1,258)	(792)	(289)
Federal research and development credits	(395)	(348)	(453)
Uncertain tax positions	283	(413)	97
Change in tax rates	(95)	80	(317)
Change in tax rates	14	(313)	235
Change in valuation allowance	7,425	1,392	1,665
Net income tax expense	5,547	413	1,284
Foreign Research and Development Incentives [Member]
Increase (decrease) in income taxes resulting from:
Other	45	59	0
Other Deductions [Member]
Increase (decrease) in income taxes resulting from:
Other	13	(13)	(3)
SAUDI ARABIA
Increase (decrease) in income taxes resulting from:
Foreign tax rate differential	$ 52	$ 0	$ 0