Stockholders' Equity and Employee Stock Option Plans RSU and RSA Activity (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
RSU and RSA activity [Abstract]
RSU/ RSA Nonvested and outstanding opening balance, Number	1,368,097	1,929,614	2,521,593
RSU/ RSA Nonvested and Outstanding Opening balance, Weighted Average Grant Date Fair Value	$ 5.22	$ 6.56	$ 8.40
RSU/ RSA, Grants in Period	1,289,138	419,056	700,987
RSU/RSA, Grants in Period, Weighted Average Grant Date Fair Value	$ 2.51	$ 2.34	$ 3.25
RSU/RSA Vested in Period	(500,528)	(522,286)	(977,149)
RSU/ RSA Vested in Period, Weighted Average Grant Date Fair Value	$ 5.78	$ 6.99	$ 8.48
RSU/ RSA Forfeited in Period	(863,278)	(458,287)	(315,817)
RSU/RSA, Forfeitures, Weighted Average Grant Date Fair Value	$ 3.69	$ 6.19	$ 7.80
RSU/ RSA Nonvested and outstanding ending balance, Number	1,293,429	1,368,097	1,929,614
RSU/ RSA Nonvested and Outstanding Closing balance, Weighted Average Grant Date Fair Value	$ 3.32	$ 5.22	$ 6.56
Total fair value of RSUs vested and released	$ 1.2	$ 1.2	$ 3.7
RSU, Vested and Expected to Vest, Outstanding, Number	1,242,853
RSU, Vested and Expected to Vest, Outstanding, Aggregate Intrinsic Value	$ 2.1
Share Price	$ 1.70us-gaap_SharePrice

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Share-based Compensation Arrangement by Share-based Payment Award, RSU, Vested and Expected to Vest, Outstanding, Aggregate Intrinsic Value

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, RSU, Vested and Expected to Vest, Outstanding, Number

+ References

No definition available.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iv)(3)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(iii)(3)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(iii)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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-Publisher FASB

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-Topic 718

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-Paragraph 2

-Subparagraph (c)(2)(iii)(1)

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(i)-(ii)

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- Definition

The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(i)-(ii)

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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- Definition

Price of a single share of a number of saleable stocks of a company.

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