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Income Taxes (Reconciliation Of The Statutory U.S. Federal Income Tax And The Income Tax Provision) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Taxes [Abstract]
Statutory rate	34.00%	34.00%	34.00%
Tax (benefit) expense at statutory rate	$ (278)	$ (1,428)	$ (5,906)
State income tax (benefit) expense	(42)	(216)	(893)
Permanent difference	1	1	3
Impact of 2017 Tax Act	5,319
Other	14
Net change in deferred tax asset valuation allowance	(5,256)	$ 1,643	14,147
Total income tax provision (benefit)	$ (242)		$ 7,351

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Income Tax Reconciliation, Permanent Difference

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

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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 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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