Operating loss carryforwards expiration year.

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Tax Cuts and Jobs Act of 2017, change in tax rate, deferred tax liability provisional income tax (expense) benefit.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards that are not subject to expiration dates.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards that are subject to expiration dates.

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No definition available.

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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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- Definition

Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount 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 increase (decrease) in the valuation allowance for deferred tax assets.

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- Definition

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The portion of the valuation allowance pertaining to the deferred tax asset representing potential future taxable deductions from net operating loss carryforwards for which it is more likely than not that a tax benefit will not be realized.

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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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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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Income Taxes (Narrative) (Details) - USD ($)	12 Months Ended
Income Taxes (Narrative) (Details) - USD ($)	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Operating Loss Carryforwards [Line Items]
U.S. federal statutory income tax rate	21.00%	35.00%	35.00%
Reduction in net deferred tax liabilities		$ 15,720,000
Increase in valuation allowance	$ 116,000	1,152,000	$ 821,000
Operating loss carryforwards, subject to expiration	2,876,000
Operating loss carryforwards, subject to carry forward indefinitely	6,657,000
Unrecognized tax benefits	157,000	157,000	$ 157,000	$ 157,000
Amount of unrecognized tax benefits which would have an impact on the effective tax rate	124,000	124,000
Interest and penalties recorded	71,000	53,000
Deferred tax assets valuation allowance	4,786,000	4,294,000
Domestic Tax Authority [Member]
Operating Loss Carryforwards [Line Items]
Loss carryforwards for federal income tax purposes	168,650,000	207,875,000
Deferred tax assets valuation allowance	$ 0	0
Domestic Tax Authority [Member] \| Minimum [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards expiration year	2034
Domestic Tax Authority [Member] \| Maximum [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards expiration year	2037
State and Local Jurisdiction [Member]
Operating Loss Carryforwards [Line Items]
Loss carryforwards for federal income tax purposes	$ 190,901,000	209,877,000
Valuation allowance for net operating loss carryforwards	$ 767,000
State and Local Jurisdiction [Member] \| Minimum [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards expiration year	2023
State and Local Jurisdiction [Member] \| Maximum [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards expiration year	2028
Foreign Tax Authority [Member]
Operating Loss Carryforwards [Line Items]
Loss carryforwards for federal income tax purposes	$ 9,533,000	7,637,000
Valuation allowance for net operating loss carryforwards	$ 2,338,000	$ 1,962,000
Foreign Tax Authority [Member] \| Minimum [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards expiration year	2018
Foreign Tax Authority [Member] \| Maximum [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards expiration year	2028