FINANCIAL ASSETS AND LIABILITIES - Gains and Losses (Details) - USD ($) $ in Millions	3 Months Ended
Jun. 30, 2022	Jun. 30, 2021
Derivative instruments in cash flow hedges
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Recognized in OCI	$ (5)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Reclassified from AOCI	1
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Amounts Excluded from Effectiveness Testing	0	$ 0
Not designated as hedging instruments - economic hedges
Derivative Instruments, Gain (Loss) [Line Items]
Net gains (loss) from derivatives	(2)
Cost of services. \| Derivative instruments in cash flow hedges
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Recognized in OCI	(5)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Reclassified from AOCI	1
Other expenses \| Foreign exchange contracts \| Not designated as hedging instruments - economic hedges
Derivative Instruments, Gain (Loss) [Line Items]
Net gains (loss) from derivatives	$ (2)

Amount of gain (loss) from excluded component of derivative hedge, recognized in earnings. Excludes recognition under systematic and rational method.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 20
-Section 45
-Paragraph 1A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121577181&loc=SL110061172-113977

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5624171-113959

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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5618551-113959

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Amount before tax and reclassification adjustments of other comprehensive income (loss) attributable to parent.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
-URI http://asc.fasb.org/extlink&oid=124509347&loc=SL7669686-108580

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