Stock-based Compensation - Equity Awards (Details) (2007 Stock Plan [Member]) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2014	Mar. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	49	490
Equity awards granted during the period, total, Grants in Period, Gross	218	529
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	2	3
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	167	36
Share-based Compensation Arrangement by Share-based Payment Award, Options, Semi-Annual Performance Period Multiplier, Maximum	2.75
Share-based Compensation Arrangement by Share-based Payment Award, Options, Performance Multiplier Maximum	2.5

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, Options, Performance Multiplier Maximum

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Options, Semi-Annual Performance Period Multiplier, Maximum

+ References

No definition available.

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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

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

+ References

No definition available.

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