Income Taxes (Effective Income Tax Rate Reconciliation) (Details)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Income tax provision, at statutory federal rate	34.00%	34.00%	34.00%
State and local income taxes, net of federal income taxes effect	6.00%	5.00%	6.00%
Credits	0.00%	0.00%	5.00%
Permanent differences	(10.00%)	(13.00%)	(7.00%)
Goodwill impairment	0.00%	0.00%	(4.00%)
Fiberxon settlement	0.00%	0.00%	0.00%
Foreign taxes at rates different than domestic rates	(4.00%)	(7.00%)	(1.00%)
Change in valuation allowance	(76.00%)	(49.00%)	(20.00%)
Change in reserve for uncertain tax positions	0.00%	(3.00%)	0.00%
Other adjustments	(5.00%)	5.00%	0.00%
Effective tax rate	(55.00%)	(28.00%)	13.00%

Effective Income Tax Rate Reconciliation, Change in Reserve For Uncertainty In Income Taxes

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Effective Income Tax Rate Reconciliation, Litigation Settlement

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Effective IncomeTax Rate Reconciliation, Permanent Differences

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

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

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Percentage 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 changes in the valuation allowance for deferred tax assets.

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Percentage 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 applicable to statutory income tax expense (benefit) outside of the country of domicile.

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Percentage 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 applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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Percentage 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 tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits.

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