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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Interest rate stated in the contractual debt agreement.

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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.

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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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The cash outflow for a financial contract that meets the hedge criteria as either cash flow hedge, fair value hedge or hedge of net investment in foreign operations.

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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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Amount of unrealized gain (loss) related to the increase or decrease in fair value of interest rate derivatives designated as cash flow hedging instruments, which was recorded in accumulated other comprehensive income to the extent that the cash flow hedge was determined to be effective.

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Long-Term Debt (Narrative) (Details) (USD $)	1 Months Ended		9 Months Ended
Long-Term Debt (Narrative) (Details) (USD $)	Oct. 31, 2011	Mar. 31, 2011	Oct. 29, 2011
Debt Instrument [Line Items]
Repayments of long-term debt	$ 100,000,000	$ 300,000,000	$ 400,000,000
Weighted Average Effective Rate			6.01%
Interest rate hedges, fair value			48,000,000
Unrealized loss on the hedges recognized as interest expense			5,000,000
Interest Rate Hedges [Member]
Debt Instrument [Line Items]
Debt issued			400,000,000
4.00% Notes Maturing On November 1, 2021 [Member]
Debt Instrument [Line Items]
Debt issued			$ 650,000,000
Debt instrument interest rate			4.00%
Debt instrument interest rate terms			semi-annual interest payments beginning May 2012
Maturity of notes			Nov. 01, 2021
Senior Notes Due 2021 [Member]
Debt Instrument [Line Items]
Weighted Average Effective Rate			4.81%