Financial Instruments and Fair Value Measurements - Summary of Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Millions	Sep. 30, 2024	Jun. 30, 2024
Assets:
Equity and other securities	$ 235	$ 214
Fair Value, Recurring
Assets:
Equity and other securities	235	214
Total assets	249	243
Liabilities:
Total liabilities	(11)	(2)
Fair Value, Recurring | Interest rate derivatives - cash flow hedges | Cash Flow Hedging
Assets:
Derivative assets	14	29
Liabilities:
Derivative liabilities	(5)	0
Fair Value, Recurring | Foreign currency derivatives - cash flow hedges | Cash Flow Hedging
Liabilities:
Derivative liabilities	(2)	0
Fair Value, Recurring | Cross currency interest rate derivatives | Cash Flow Hedging
Liabilities:
Derivative liabilities	(4)	(2)
Fair Value, Recurring | Level 1
Assets:
Equity and other securities	65	53
Total assets	65	53
Liabilities:
Total liabilities	0	0
Fair Value, Recurring | Level 1 | Interest rate derivatives - cash flow hedges | Cash Flow Hedging
Assets:
Derivative assets	0	0
Liabilities:
Derivative liabilities	0	0
Fair Value, Recurring | Level 1 | Foreign currency derivatives - cash flow hedges | Cash Flow Hedging
Liabilities:
Derivative liabilities	0	0
Fair Value, Recurring | Level 1 | Cross currency interest rate derivatives | Cash Flow Hedging
Liabilities:
Derivative liabilities	0	0
Fair Value, Recurring | Level 2
Assets:
Equity and other securities	46	39
Total assets	60	68
Liabilities:
Total liabilities	(11)	(2)
Fair Value, Recurring | Level 2 | Interest rate derivatives - cash flow hedges | Cash Flow Hedging
Assets:
Derivative assets	14	29
Liabilities:
Derivative liabilities	(5)	0
Fair Value, Recurring | Level 2 | Foreign currency derivatives - cash flow hedges | Cash Flow Hedging
Liabilities:
Derivative liabilities	(2)	0
Fair Value, Recurring | Level 2 | Cross currency interest rate derivatives | Cash Flow Hedging
Liabilities:
Derivative liabilities	(4)	(2)
Fair Value, Recurring | Level 3
Assets:
Equity and other securities	124	122
Total assets	124	122
Liabilities:
Total liabilities	0	0
Fair Value, Recurring | Level 3 | Interest rate derivatives - cash flow hedges | Cash Flow Hedging
Assets:
Derivative assets	0	0
Liabilities:
Derivative liabilities	0	0
Fair Value, Recurring | Level 3 | Foreign currency derivatives - cash flow hedges | Cash Flow Hedging
Liabilities:
Derivative liabilities	0	0
Fair Value, Recurring | Level 3 | Cross currency interest rate derivatives | Cash Flow Hedging
Liabilities:
Derivative liabilities	$ 0	$ 0