Debentures - Impact of Changes in Fair Value of Debentures (Details) - USD ($) $ in Millions	12 Months Ended
Feb. 28, 2021	Feb. 29, 2020	Feb. 28, 2019
Debt Instrument [Line Items]
Income (charge) associated with the change in fair value from non-credit components recorded in the consolidated statements of operations	$ (372)	$ 66	$ 117
3.75% Debenture
Debt Instrument [Line Items]
Income (charge) associated with the change in fair value from non-credit components recorded in the consolidated statements of operations	(19)	66	117
Income (charge) associated with the change in fair value from instrument-specific credit components recorded in AOCL	15	(7)	0
Realized charges associated with the change in fair value from credit components recorded in the consolidated statements of operations on redemption	(6)	0	0
Realized charges associated with the change in fair value from credit components released from AOCL on redemption	6	0	0
Debenture total fair value adjustment	(4)	59	117
1.75% Debenture
Debt Instrument [Line Items]
Income (charge) associated with the change in fair value from non-credit components recorded in the consolidated statements of operations	(347)	0	0
Income (charge) associated with the change in fair value from instrument-specific credit components recorded in AOCL	(8)	0	0
Debenture total fair value adjustment	$ (355)	$ 0	$ 0

Debenture total fair value adjustment

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- Definition

Realized charges associated with the change in fair value from credit components recorded in the consolidated statement of operations on redemption

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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- Definition

For each line item in the statement of financial position, the amounts of gains and losses from fair value changes included in earnings.

+ References

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- Definition

Amount, before tax, of reclassification adjustment from accumulated other comprehensive income (loss) for unrealized gain (loss) from increase (decrease) in instrument-specific credit risk, realized upon derecognition of financial liability measured under fair value option.

+ References

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- Definition

Amount, before tax and reclassification adjustment, of unrealized gain (loss) from increase (decrease) in instrument-specific credit risk of financial liability measured under fair value option.

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