v2.3.0.15

Cash Convertible Senior Notes and Related Transactions, Textuals (Details) (USD $)	9 Months Ended		3 Months Ended		3 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011 Convertible Debt [Member]	Mar. 29, 2010 Convertible Debt [Member]	Mar. 31, 2010 Call Options [Member]	Mar. 31, 2010 Warrant Transactions [Member]
Cash Convertible Senior Notes and Related Transactions (Textuals) [Abstract]
Aggregate principal amount of notes pursuant to an indenture				$ 175,000,000
Proceed from Issuance of Notes net of expenses			169,100,000
Stated interest rate of notes pursuant to an indenture				4.50%
Debt discount on notes				38,100,000
Capitalized deferred financing costs				5,900,000
Effective interest rate of the Notes				11.00%
Repurchase Price of Notes				100.00%
Conversion rate of common stock shares per $1,000 of principal amount				20.6949
Principal amount in conversion feature				1,000
Initial conversion price of note				$ 48.32
Purchase of call option in connection with issuance of cash convertible senior notes	0	31,400,000			31,400,000
Common stock sold related to option counterparties net share-settled warrants	3,600,000					3,600,000
Amount paid by Option Counterparties to Company for Warrants	$ 0	$ 14,300,000				$ 14,300,000
Initial strike price per share	$ 61.36					$ 61.36

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