Convertible Notes Tender Offer (Detail) (USD $) In Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2011
Loss on extinguishment of debt:
Non-cash portion of loss on extinguishment		$ 21,822
Pre-tax loss on extinguishment	24,238	24,238
4.5% Convertible Notes due 2012
Cash paid to repurchase principal:
Allocated to liability component	231,331
Allocated to equity component	1,632
Cash paid to repurchase principal	232,963
Carrying value of liability component tendered:
Principal amount of Convertible Notes tendered	225,085
Pro rata share of original issue discount	(13,429)
Debt Instrument, Convertible, Carrying Amount of The Liability Component	211,656	211,656
Loss on extinguishment of debt:
Excess of liability component over carrying value	19,675
Write-off of pro rata share of debt issuance costs	2,147
Non-cash portion of loss on extinguishment	21,822
Transaction costs and fees paid	2,416
Pre-tax loss on extinguishment	$ 24,238

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Gain (Loss) on Extinguishment of Debt Before Transaction Costs

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Gain (Loss) on Extinguishment of Debt, Payments Under (Over) Carrying Value

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Write Off of Debt Discount

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Gross amount of debt extinguished.

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Amount represents the difference between the fair value of the payments made and the carrying amount of the debt at the time of its extinguishment.

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The cash outflow to reacquire other equity not otherwise defined in the taxonomy.

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The cash outflow for incremental, external costs directly pertaining to an early extinguishment of debt, including legal costs and prepayment penalties, and excluding interest and repayment of debt principal.

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The cash outflow from the repayment of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

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