Cash Convertible Senior Notes and Related Transactions.

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Debt instruments convertible terms of conversion feature.

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Price as percentage of the price of the principal amount of the Notes plus any accrued and unpaid interest for the repurchase of Notes.

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Principal amount in conversion feature

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

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The specified number of securities that each class of warrants or rights outstanding give the holder the right but not the obligation to purchase from the issuer at a specific price, on or before a certain date.

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

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The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Interest rate stated in the contractual debt agreement.

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The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

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For an unclassified balance sheet, the carrying amount (net of accumulated amortization) as of the balance sheet date of capitalized costs associated with the issuance of debt instruments (for example, legal, accounting, underwriting, printing, and registration costs) that will be charged against earnings over the life of the debt instruments to which such costs pertain.

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The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

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The cash inflow from issuance of rights to purchase common shares at predetermined price (usually issued together with corporate debt).

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The net cash inflow or outflow from other financing activities. This element is used when there is not a more specific and appropriate element in the taxonomy.

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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