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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Antidilution
-URI http://asc.fasb.org/extlink&oid=6505113

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Diluted Earnings Per Share
-URI http://asc.fasb.org/extlink&oid=6510752

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Contingent Stock Agreement
-URI http://asc.fasb.org/extlink&oid=6508534

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(4))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(2))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
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- Definition

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

+ References

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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Publisher FASB
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- Definition

Face (par) amount of the original debt instrument that was repurchased.

+ References

No definition available.

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- Definition

The per share price of the Company's stock at which the contract holder of the freestanding contract has the right to purchase or sell the Company's stock at a future date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- Definition

Exercise or strike price stated in the contract for options indexed to the issuer's equity shares.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
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- Definition

The sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation.

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(Loss) Earnings Per Share (Narrative) (Details)	1 Months Ended			3 Months Ended		9 Months Ended
(Loss) Earnings Per Share (Narrative) (Details)	Jun. 30, 2016 USD ($) $ / shares	Jan. 31, 2015 $ / shares	Jun. 30, 2012 $ / shares shares	Sep. 30, 2016 shares	Sep. 30, 2015 shares	Sep. 30, 2016 shares	Sep. 30, 2015 shares
Schedule of Earnings per Share Basic and Diluted [Line Items]
Antidilutive shares excluded from computation of diluted loss per share (shares)				3,930,938	4,816,237		2,677,921
Shares issuable upon conversion, included in diluted shares (in shares)				0	0	3,209,000	0
Convertible Senior Notes Due 2023 [Member] \| Senior Notes [Member]
Schedule of Earnings per Share Basic and Diluted [Line Items]
Conversion ratio	0.0204198
Conversion price (USD per share) \| $ / shares	$ 48.97
Convertible Senior Notes Due 2022 [Member] \| Senior Notes [Member]
Schedule of Earnings per Share Basic and Diluted [Line Items]
Conversion ratio		0.0298806
Conversion price (USD per share) \| $ / shares		$ 33.47
Shares issuable upon conversion, included in diluted shares (in shares)						647,645
Convertible Senior Notes Due 2017 [Member] \| Senior Notes [Member]
Schedule of Earnings per Share Basic and Diluted [Line Items]
Conversion ratio			0.0358038
Conversion price (USD per share) \| $ / shares			$ 27.93
Shares issuable upon conversion, included in diluted shares (in shares)						781,558
Debt, aggregate principal amount repurchased \| $	$ 220,000,000
Convertible Senior Notes Due 2017 [Member] \| Senior Notes [Member] \| 2017 Warrants [Member]
Schedule of Earnings per Share Basic and Diluted [Line Items]
Shares issuable upon conversion, included in diluted shares (in shares)						80,398
Warrants for shares of common stock (shares)			2,000,000
Strike price, warrant (USD per share) \| $ / shares			$ 34.20
Stock options [Member]
Schedule of Earnings per Share Basic and Diluted [Line Items]
Antidilutive shares excluded from computation of diluted loss per share (shares)						3,109,274
Unvested restricted stock [Member]
Schedule of Earnings per Share Basic and Diluted [Line Items]
Antidilutive shares excluded from computation of diluted loss per share (shares)						9,136
Call Option [Member] \| Convertible Senior Notes Due 2023 [Member] \| Senior Notes [Member]
Schedule of Earnings per Share Basic and Diluted [Line Items]
Strike price, capped calls (USD per share) \| $ / shares	$ 48.97
Cap price (USD per share) \| $ / shares	$ 64.68