Stock-based Compensation - Equity Awards (Details) - 2007 Stock Plan [Member] - $ / shares shares in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, grants in period	1,036	555
Total grants in period	1,716	2,010
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity instruments other than options, grants in period	0	5
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	50.00%
Equity instruments other than options, grants in period	680	1,450
$3.45 Average Closing Stock Price [Member] \| Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percent	50.00%
Duration of trading period stock price must be maintained	30 days
Required average closing stock price (usd per share)	$ 3.45
Award performance period	3 years
$4.25 Average Closing Stock Price [Member] \| Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percent	50.00%
Duration of trading period stock price must be maintained	30 days
Required average closing stock price (usd per share)	$ 4.25
Award performance period	4 years

Equity awards granted during the period, total, Grants in Period, Gross

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Award Performance Period

+ References

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Percent

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Required Average Closing Stock Price Per Share

+ References

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Duration of Trading Period Stock Price Must be Maintained

+ References

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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

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

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- Definition

Percentage of vesting of share-based compensation awards.

+ 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 (a)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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