Fair Value Measurements - Summary of Changes in Fair Value of Company's Level 3 Assets (Detail) - USD ($) $ in Millions	12 Months Ended
Feb. 29, 2020	Feb. 28, 2019
Cash and Cash Equivalents [Abstract]
Beginning Balance	$ 19	$ 20
Principal repayments	19	1
Ending Balance	$ 0	$ 19
Investments that are communicated to the third party for consideration of reasonableness, threshold limit for fair values	0.50%

Investments That Are Communicated To Third Party For Consideration Of Reasonableness Threshold Limit For Fair Value

No definition available.

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- References

No definition available.

+ Details

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- Definition

Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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