Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Taxes [Abstract]
Net operating loss carryforwards	$ 93,900
Impact of federal tax law change	211	$ (53,348)
Unrecognized tax benefits that would impact effective tax rate	5,000	6,500	$ 7,600
Net increase (decrease) in unrecognized tax benefit	(1,500)	(1,100)	4,000
Gross unrecognized tax benefits	$ 4,998	$ 6,495	$ 7,574	$ 3,612

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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 income tax rates.

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

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Amount of unrecognized tax benefits.

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Amount of increase (decrease) in unrecognized tax benefits attributable to uncertain tax positions taken in tax returns.

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

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