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Long-term Corporate Debt and Borrowing Arrangements - Schedule of Long-Term Debt (Detail) - USD ($) $ in Millions	Dec. 31, 2021	Sep. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Aug. 31, 2020	May 31, 2020	Jul. 31, 2019	Oct. 31, 2018	Mar. 31, 2017	Sep. 30, 2016	Mar. 31, 2016	Mar. 31, 2015
Debt Instrument [Line Items]
Deferred financing fees	$ (48)			$ (48)
Total	4,009			4,210
Less: Short-term debt and current portion of long-term debt	19			19
Long-term debt	3,990			4,191
Other Long-Term Debt
Debt Instrument [Line Items]
Long-term debt	$ 19			24
Senior Notes \| 6.375% Senior Notes
Debt Instrument [Line Items]
Debt instrument interest percentage	6.375%		6.375%								6.375%
Long-term debt	$ 0			350
Senior Notes \| 4.125% euro-denominated Senior Notes
Debt Instrument [Line Items]
Debt instrument interest percentage	4.125%									4.125%
Long-term debt	$ 341			366
Senior Notes \| 5.250% Senior Notes
Debt Instrument [Line Items]
Debt instrument interest percentage	5.25%	5.25%	5.25%									5.25%
Long-term debt	$ 0			375
Senior Notes \| 4.500% euro-denominated Senior Notes
Debt Instrument [Line Items]
Debt instrument interest percentage	4.50%								4.50%
Long-term debt	$ 284			305
Senior Notes \| 10.500% Senior Secured Notes
Debt Instrument [Line Items]
Debt instrument interest percentage	10.50%		10.50%			10.50%
Long-term debt	$ 0			487
Senior Notes \| 4.750% euro-denominated Senior Notes
Debt Instrument [Line Items]
Debt instrument interest percentage	4.75%							4.75%
Long-term debt	$ 398			428
Senior Notes \| 5.750% Senior Notes
Debt Instrument [Line Items]
Debt instrument interest percentage	5.75%				5.75%		5.75%
Long-term debt	$ 728			724
Senior Notes \| 4.750% Senior Notes
Debt Instrument [Line Items]
Debt instrument interest percentage	4.75%		4.75%
Long-term debt	$ 500			0
Senior Notes \| 5.375% Senior Notes
Debt Instrument [Line Items]
Debt instrument interest percentage	5.375%		5.375%
Long-term debt	$ 600			0
Loans Payable \| Floating Rate Term Loan
Debt Instrument [Line Items]
Long-term debt	$ 1,187			$ 1,199