Income Taxes (Details) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Income Taxes [Abstract]
(Provision) benefit for income taxes	$ (20,000)	$ (6,000)	$ 177,000	$ (65,000)
Deferred income taxes (Note 7)	603,000		603,000		$ 818,000
Unrecognized tax benefits	660,000		660,000		648,000
Interest and penalties	$ 291,000		$ 291,000		$ 278,000

Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences, with jurisdictional netting and classified as noncurrent.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of unrecognized tax benefits.

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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