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The exercise price of each class of warrants or rights outstanding.

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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)(4))

-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690

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-Name Regulation S-X (SX)

-Number 210

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-Article 4

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 20

-Section 50

-Paragraph 5

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870

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-Name FASB Staff Position (FSP)

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Interest rate stated in the contractual debt agreement.

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Description of the maturity date of the debt instrument including whether the debt matures serially and, if so, a brief description of the serial maturities.

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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-Publisher FASB

-Name Accounting Standards Codification

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-Name Statement of Financial Accounting Standard (FAS)

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Net Incone Per Shares (Narrative) (Details) (USD $)					1 Months Ended	3 Months Ended
Net Incone Per Shares (Narrative) (Details) (USD $)	Jun. 30, 2013	Mar. 31, 2013	Jun. 30, 2013 Warrants	Jul. 14, 2011 Warrants	Jul. 31, 2011 0.75% Convertible Senior Notes Due 2016	Jun. 30, 2013 0.75% Convertible Senior Notes Due 2016	Jul. 14, 2011 0.75% Convertible Senior Notes Due 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share
Contractual interest rate of 0.75% Convertible Senior Notes due 2016	0.75%	0.75%				0.75%	0.75%
Convertible Senior Notes due description					2016	2016
Conversion price per share						$ 31.74	$ 31.74
Warrants, Conversion price per share			41.14	41.14