Debt (Schedule Of Debt) (Details) - USD ($) $ in Thousands	Aug. 31, 2017	Feb. 28, 2017
Debt Instrument [Line Items]
Finance and Capital Lease Obligations	$ 502,502	$ 496,136
Non-Recourse Debt	11,303,502	10,742,425
Total debt	12,624,275	12,193,623
Less: current portion	(366,690)	(343,266)
Unamortized Debt Issuance Expense	(23,581)	(23,919)
Long-term debt, net	12,234,004	11,826,438
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long-term Debt	18,271	155,062
Term Loan [Member]
Debt Instrument [Line Items]
Long-term Debt	300,000	300,000
3.86% senior notes dues 2023 [Member]
Debt Instrument [Line Items]
Long-term Debt	100,000	100,000
4.17% senior notes due 2026 [Member]
Debt Instrument [Line Items]
Long-term Debt	200,000	200,000
4.27% senior notes due 2028 [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 200,000	$ 200,000

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of debt for which creditor does not have general recourse to the debtor but rather has recourse only to the property used for collateral in the transaction or other specific property.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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