Income Taxes (Details Textual) - USD ($)	1 Months Ended	12 Months Ended
	Dec. 22, 2017	Dec. 31, 2018	Dec. 31, 2017
Income tax expense		$ 24,000	$ 88,000
State tax net of federal benefit		(7.70%)	(4.90%)
Valuation allowance		$ (61,512,000)	$ (65,817,000)
Deferred tax assets		10,300,000
Amount of unrecognized or expected tax benefits recorded in financial statement		$ 1,100,000	1,100,000
Investment tax credits and research and development credits scheduled to expire		2019
Increase (decrease) in foreign with holding taxes payable		$ 24,000	$ 129,000
Deferred tax assets and liabilities		10,300,000
Research [Member]
Tax credit carry forward amount		66,000
Investment Credit [Member]
Tax credit carry forward amount		23,000
Federal [Member]
Net operating loss carryforward		181,100,000
Tax credit carry forward amount		$ 662,000
Operating loss carry forwards expiration year		2021
Illinois NOL carryforwards [Member]
Net operating loss carryforward		$ 195,000,000
Operating loss carry forwards expiration year		2020
Maximum [Member]
U.S. corporate tax rate	35.00%
Repatriation tax	$ 5,000,000
Minimum [Member]
U.S. corporate tax rate	21.00%
Repatriation tax	$ 3,900,000