Schedule of Earnings per Share, Basic and Diluted [Line Items]

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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-Publisher FASB

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-Glossary Contingent Stock Agreement

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

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- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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- Definition

The price per share of the conversion feature embedded in the debt instrument.

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- Definition

Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

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

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-Glossary Financing Activities

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Number of new stock issued during the period.

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Loss per Share (Narrative) (Details)	1 Months Ended			3 Months Ended		9 Months Ended
Loss per Share (Narrative) (Details)	Aug. 31, 2015 USD ($) shares	Jan. 31, 2015 USD ($) $ / shares	Jun. 30, 2012 USD ($) $ / shares shares	Sep. 30, 2015 USD ($) shares	Sep. 30, 2014 shares	Sep. 30, 2015 USD ($) shares	Sep. 30, 2014 USD ($) shares	Dec. 31, 2014 USD ($)
Schedule of Earnings per Share Basic and Diluted [Line Items]
Issuance of common stock (in shares)	944,537
Proceeds from issuances of common stock \| $	$ 30,000,000					$ 89,718,000	$ 13,682,000
2017 Warrants [Member]
Schedule of Earnings per Share Basic and Diluted [Line Items]
Warrants for shares of common stock (shares)			9,800,000
Strike price (USD per share) \| $ / shares			$ 34.20
Convertible Senior Notes Due 2022 [Member] \| Senior Notes [Member]
Schedule of Earnings per Share Basic and Diluted [Line Items]
Convertible senior notes \| $		$ 400,000,000		$ 400,000,000		400,000,000		$ 0
Interest rate		2.50%
Conversion ratio		0.0298806
Conversion price (USD per share) \| $ / shares		$ 33.47
Convertible Senior Notes Due 2017 [Member] \| Senior Notes [Member]
Schedule of Earnings per Share Basic and Diluted [Line Items]
Convertible senior notes \| $			$ 275,000,000	$ 275,000,000		$ 275,000,000		$ 275,000,000
Interest rate			1.375%
Conversion ratio			0.0358038
Conversion price (USD per share) \| $ / shares			$ 27.93
Option [Member]
Schedule of Earnings per Share Basic and Diluted [Line Items]
Antidilutive shares excluded from computation of diluted loss per share (shares)				1,737,569	1,280,612	1,454,852	1,611,940
Restricted Stock [Member]
Schedule of Earnings per Share Basic and Diluted [Line Items]
Antidilutive shares excluded from computation of diluted loss per share (shares)				257,819	252,943	264,206	286,867
Convertible Notes [Member] \| Convertible Senior Notes Due 2022 [Member] \| Senior Notes [Member]
Schedule of Earnings per Share Basic and Diluted [Line Items]
Antidilutive shares excluded from computation of diluted loss per share (shares)				555,859		185,286
Convertible Notes [Member] \| Convertible Senior Notes Due 2017 [Member] \| Senior Notes [Member]
Schedule of Earnings per Share Basic and Diluted [Line Items]
Antidilutive shares excluded from computation of diluted loss per share (shares)				2,011,844		689,195
Warrant [Member] \| 2017 Warrants [Member]
Schedule of Earnings per Share Basic and Diluted [Line Items]
Antidilutive shares excluded from computation of diluted loss per share (shares)				253,146		84,382