SUMMARY OF ACCOUNTING POLICIES - Concentration of Credit Risk (Details) - USD ($) $ in Millions	12 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2019
Allowance for doubtful accounts
Balance at Beginning of Year	$ 96	$ 91	$ 60
Charged to Costs and Expenses	5	24	42
Deductions/ Write-Offs	(40)	(19)	(11)
Balance at End of Year	$ 61	$ 96	$ 91
Customer one \| Accounts Receivable \| C T G
Allowance for doubtful accounts
Concentration risk percentage	11.00%	10.00%	11.00%
Ten largest customers \| Net sales
Allowance for doubtful accounts
Concentration risk percentage	36.00%	39.00%	43.00%

Amount of allowance for credit loss on accounts receivable, classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of direct write-downs of accounts receivable charged against the allowance.

+ References

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of expense (reversal of expense) for expected credit loss on accounts receivable.

+ References

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