Stock Incentive Plans - Securities To Be Issued and Remaining Available For Future Issuance (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
2004 LTIP [Member] \| Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of securities to be issued upon exercise of outstanding options and vesting of RSUs	2,252
Weighted-average exercise price of outstanding options and vesting of RSUs (in dollars per share)	$ 9.60	$ 15.85
Number of securities remaining available for future issuance under equity compensation plans (excluding securities reflected in column 1)	0
2005 LTIP [Member] \| Restricted stock units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of securities to be issued upon exercise of outstanding options and vesting of RSUs	6,106
Weighted-average exercise price of outstanding options and vesting of RSUs (in dollars per share)	$ 0.01
Number of securities remaining available for future issuance under equity compensation plans (excluding securities reflected in column 1)	0
2007 LTIP [Member] \| Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average exercise price of outstanding options and vesting of RSUs (in dollars per share)	$ 10.48	$ 12.37
2007 LTIP [Member] \| Stock Options, Restricted Stock Units and Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of securities to be issued upon exercise of outstanding options and vesting of RSUs	42,312
Weighted-average exercise price of outstanding options and vesting of RSUs (in dollars per share)	$ 10.28
Number of securities remaining available for future issuance under equity compensation plans (excluding securities reflected in column 1)	0
2010 LTIP [Member] \| Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average exercise price of outstanding options and vesting of RSUs (in dollars per share)	$ 16.39	$ 16.39
2010 LTIP [Member] \| Stock Options, Restricted Stock Units and Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of securities to be issued upon exercise of outstanding options and vesting of RSUs	347,414
Weighted-average exercise price of outstanding options and vesting of RSUs (in dollars per share)	$ 0.72
Number of securities remaining available for future issuance under equity compensation plans (excluding securities reflected in column 1)	1,412,522

Share-based Compensation Arrangement by Share-based Payment Award, Number of Securities To Be Issued Upon Exercise of Outstanding Options, Warrants and Rights

No definition available.

+ Details

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option 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)(1)(i)

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

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