Stock Based Compensation Nonvested Stock Option Activity (Details) (USD $)	3 Months Ended	12 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares [Roll Forward]
Granted	1,348,504	1,389,452
Nonvested Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares [Roll Forward]
Stock Option Shares Outstanding, Beginning Balance	2,770,662	3,110,523
Granted	1,348,504	1,389,452
Vested	(1,313,007)	(1,522,152)
Forfeited	(9,729)	(207,161)
Stock Option Shares Outstanding, Ending Balance	2,796,430	2,770,662
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Nonvested Weighted Average Grant Date Fair Value, Beginning balance	3.74	4.69
Granted	3.08	3.00
Vested	4.31	4.92
Forfeited	3.35	4.38
Nonvested Weighted Average Grant Date Fair Value, Ending balance	3.16	3.74

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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

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

+ References

No definition available.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ 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 (d)(1)

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

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- Definition

Number of non-vested options outstanding.

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- Definition

Weighted average grant-date fair value of non-vested options forfeited.

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- Definition

Weighted average grant-date fair value of non-vested options outstanding.

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- Definition

Number of options vested.

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Weighted average grant-date fair value of options vested.

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