Condensed Consolidated Statement of Shareholder's Equity (unaudited) - USD ($) $ in Millions	Total	Common Stock	Additional Paid-in Capital	(Accumulated Deficit)/Retained Earnings	Accumulated Other Comprehensive Loss (AOCI)	Non- controlling Interests
Beginning balance, shares at Mar. 31, 2022		1,100
Beginning balance at Mar. 31, 2022	$ 2,509	$ 0	$ 1,308	$ 1,814	$ (620)	$ 7
Increase (Decrease) in Stockholders' Equity
Net income attributable to our common shareholder	502			502
Net loss attributable to noncontrolling interests	(1)					1
Currency translation adjustment included in other comprehensive income (loss)	(146)				(146)
Change in fair value of effective portion of cash flow hedges, net of tax provision (benefit) included in other comprehensive (loss) income	480				480
Change in pension and other benefits, net of tax provision included in other comprehensive income (loss)	7				7	0
Return of capital to our common shareholder	(100)		(100)
Ending balance, shares at Dec. 31, 2022		1,100
Ending balance at Dec. 31, 2022	3,251	$ 0	1,208	2,316	(279)	6
Beginning balance, shares at Sep. 30, 2022		1,100
Beginning balance at Sep. 30, 2022	3,150	$ 0	1,208	2,304	(368)	6
Increase (Decrease) in Stockholders' Equity
Net income attributable to our common shareholder	12			12
Net loss attributable to noncontrolling interests	0
Currency translation adjustment included in other comprehensive income (loss)	215				215
Change in fair value of effective portion of cash flow hedges, net of tax provision (benefit) included in other comprehensive (loss) income	(121)				(121)
Change in pension and other benefits, net of tax provision included in other comprehensive income (loss)	(5)				(5)	0
Ending balance, shares at Dec. 31, 2022		1,100
Ending balance at Dec. 31, 2022	3,251	$ 0	1,208	2,316	(279)	6
Beginning balance, shares at Mar. 31, 2023		1,100
Beginning balance at Mar. 31, 2023	3,454	$ 0	1,208	2,472	(238)	12
Increase (Decrease) in Stockholders' Equity
Net income attributable to our common shareholder	434			434
Net loss attributable to noncontrolling interests	0
Currency translation adjustment included in other comprehensive income (loss)	61				61
Change in fair value of effective portion of cash flow hedges, net of tax provision (benefit) included in other comprehensive (loss) income	(56)				(56)
Change in pension and other benefits, net of tax provision included in other comprehensive income (loss)	(7)				(6)	(1)
Ending balance, shares at Dec. 31, 2023		1,100
Ending balance at Dec. 31, 2023	3,886	$ 0	1,208	2,906	(239)	11
Beginning balance, shares at Sep. 30, 2023		1,100
Beginning balance at Sep. 30, 2023	3,623	$ 0	1,208	2,785	(382)	12
Increase (Decrease) in Stockholders' Equity
Net income attributable to our common shareholder	121			121
Net loss attributable to noncontrolling interests	0
Currency translation adjustment included in other comprehensive income (loss)	140				140
Change in fair value of effective portion of cash flow hedges, net of tax provision (benefit) included in other comprehensive (loss) income	4				4
Change in pension and other benefits, net of tax provision included in other comprehensive income (loss)	(2)				(1)	(1)
Ending balance, shares at Dec. 31, 2023		1,100
Ending balance at Dec. 31, 2023	$ 3,886	$ 0	$ 1,208	$ 2,906	$ (239)	$ 11