Amount refers to common stock par value under sales agreement.

No definition available.

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- Definition

Represents the maximum proceeds from sale of common stock under equity offering program.

+ References

No definition available.

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- Definition

The cash inflow from the additional capital contribution to the entity, net of related expenses.

+ References

No definition available.

+ Details

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- Definition

Represents the remaining proceeds from sale of common stock under equity offering program.

+ References

No definition available.

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- Definition

Face amount or stated value per share of common stock.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

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-Publisher SEC

-Name Regulation S-X (SX)

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

+ References

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- Definition

The cash inflow from the additional capital contribution to the entity.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

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- Definition

Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Stock Split

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-Publisher FASB

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-Topic 505

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-Subparagraph (SAB TOPIC 4.C)

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- Definition

Number of new stock issued during the period.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

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-Section 04

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

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- Definition

Reduction in the number of shares during the period as a result of a reverse stock split.

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-Publisher FASB

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Stockholders Equity - Stock Issuances - Additional Information (Details) (USD $) In Millions, except Share data, unless otherwise specified	1 Months Ended			3 Months Ended	12 Months Ended
	Feb. 28, 2015	Oct. 31, 2013	May 31, 2012	Mar. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Mar. 31, 2013
Stockholders Equity Note [Line Items]
Reverse stock split ratio				0.0625
Common stock, shares authorized (in shares)				170,000,000us-gaap_CommonStockSharesAuthorized	170,000,000us-gaap_CommonStockSharesAuthorized
Common stock, par value (in dollars per share)				$ 0.01	$ 0.01
Number of fractional shares were issued in connection with the reverse stock split				0
Common stock sold through the program (in shares)	2,500,000	1,300,000	1,000,000
ATM Programs [Member] \| Cowen and Company, LLC [Member]
Stockholders Equity Note [Line Items]
Common stock, par value under sales agreement (in dollars per share)							$ 0.01
Aggregate proceeds from sale of common stock under equity offering program, maximum							$ 50.0
Common stock sold through the program (in shares)					1,000,000	1,000,000
Proceeds from issuance of common stock					4.8	5.0
Proceeds of common stock issued, net of related expenses					4.7	4.8
Aggregate proceeds from sale of common stock under equity offering program, remaining				$ 39.9