Summary of Significant Accounting Policies Computation of Basic and Diluted net loss per share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended	12 Months Ended
Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Computation of Basic and Diluted net loss Per Share [Abstract]
Income (Loss) from Continuing Operations Attributable to Parent	$ (2,553)	$ (7,226)	$ (3,272)	$ (2,560)	$ (1,537)	$ (3,510)	$ (1,552)	$ (8,140)	$ (15,611)	$ (14,739)	$ (12,818)
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent	0	(1,962)	(5,340)	(1,413)	(2,486)	(3)	725	(1,107)	(8,715)	(2,871)	0
Net Income (Loss) Attributable to Parent	$ (2,553)us-gaap_NetIncomeLoss	$ (9,188)us-gaap_NetIncomeLoss	$ (8,612)us-gaap_NetIncomeLoss	$ (3,973)us-gaap_NetIncomeLoss	$ (4,023)us-gaap_NetIncomeLoss	$ (3,513)us-gaap_NetIncomeLoss	$ (827)us-gaap_NetIncomeLoss	$ (9,247)us-gaap_NetIncomeLoss	$ (24,326)us-gaap_NetIncomeLoss	$ (17,610)us-gaap_NetIncomeLoss	$ (12,818)us-gaap_NetIncomeLoss
Weighted Average Number of Shares Outstanding, Basic	43,904,000	43,507,000	43,325,000	43,264,000	43,252,000	43,184,000	43,000,000	42,929,000	43,502,000	43,092,000	42,650,000
Weighted Average Number Diluted Shares Outstanding Adjustment									0	0	0
Weighted Average Number of Shares Outstanding, Diluted	43,904,000	43,507,000	43,325,000	43,264,000	43,252,000	43,184,000	43,000,000	42,929,000	43,502,000	43,092,000	42,650,000
Income (Loss) from Continuing Operations, Per Basic and Diluted Share	$ (0.06)	$ (0.17)	$ (0.08)	$ (0.06)	$ (0.04)	$ (0.08)	$ (0.04)	$ (0.19)	$ (0.36)	$ (0.34)	$ (0.30)
Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Basic and Diluted Share	$ 0.00	$ (0.05)	$ (0.12)	$ (0.03)	$ (0.06)	$ 0.00	$ 0.02	$ (0.03)	$ (0.20)	$ (0.07)	$ 0.00
Stock Awards Excluded from Computation of Earnings Per Share Amount									4,061,346	5,472,946	5,868,929
Earnings Per Share, Basic and Diluted	$ (0.06)us-gaap_EarningsPerShareBasicAndDiluted	$ (0.21)us-gaap_EarningsPerShareBasicAndDiluted	$ (0.20)us-gaap_EarningsPerShareBasicAndDiluted	$ (0.09)us-gaap_EarningsPerShareBasicAndDiluted	$ (0.09)us-gaap_EarningsPerShareBasicAndDiluted	$ (0.08)us-gaap_EarningsPerShareBasicAndDiluted	$ (0.02)us-gaap_EarningsPerShareBasicAndDiluted	$ (0.22)us-gaap_EarningsPerShareBasicAndDiluted	$ (0.56)us-gaap_EarningsPerShareBasicAndDiluted	$ (0.41)us-gaap_EarningsPerShareBasicAndDiluted	$ (0.30)us-gaap_EarningsPerShareBasicAndDiluted

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Stock awards excluded from computation of earnings amount.

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The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Amount of income (loss) from continuing operations attributable to the parent. Also defined as revenue less expenses and taxes from ongoing operations before extraordinary items but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests.

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The amount of net income (loss) from continuing operations per each basic and diluted share of common stock or unit when the per share amount is the same for both basic and diluted shares.

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Amount of income (loss) from a disposal group, net of income tax, reported as a separate component of income before extraordinary items after deduction or consideration of the amount allocable to noncontrolling interests. Includes, net of tax, income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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Per basic and diluted share amount, after tax, of income (loss) from the day-to-day business activities of the discontinued operation and gain (loss) from the disposal of the discontinued operation, when the per share amount is the same.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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The sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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