Indebtedness (Senior Subordinated Notes Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended	9 Months Ended
Dec. 31, 2011	Dec. 31, 2011 Senior Subordinated Notes [Member]	Dec. 31, 2011 Senior Subordinated Notes [Member] 7.125% Senior Subordinated Notes Maturing October 2018 [Member]
Debt Instrument [Line Items]
Senior Notes			$ 215
Maturity date		Oct. 01, 2018
Interest rate		7.125%
Interest payable terms			semi-annually on April 1 and October 1 of each year
Senior notes call feature description	103.563% of the principal amount		The 2018 Notes have a redemption provision, which permits the Company, at its option, to call the 2018 Notes at scheduled dates and prices
First scheduled optional redemption date		Oct. 01, 2013
Percentage of price in excess of principal on redemption		103.563%

Debt Instrument, Call Feature, Cost In Excess Of Principle Percentage

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- Definition

The earliest date, before maturity, on which the issuer can call the outstanding debt instrument for repayment or conversion to equity, which may be presented in a variety of ways (year only, month and year, day, month and year, quarter, etc.).

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Description of a feature that permits the issuer of the debt to repay or convert it before the stated maturity date (early retirement date). The description may include such items as the call price, the period that the issuer can call the debt, including the earliest call date, and other significant terms of the call feature, which may include the debt holders' ability to convert the debt to equity if the call option is exercised and contingent events that trigger the issuer's ability to call the debt.

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-Publisher FASB

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-Topic 942

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- Definition

Interest rate stated in the contractual debt agreement.

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- Definition

Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets.

+ References

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-Number 129

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- Definition

Date when the debt instrument is scheduled to be fully repaid, which may be presented in a variety of ways (year, month and year, day, month and year, quarter, etc.).

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-Name Statement of Financial Accounting Standard (FAS)

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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