Financial Instruments and Fair Value Measurements - Summary of Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Millions	Mar. 31, 2024	Jun. 30, 2023
Assets:
Equity and other securities	$ 225	$ 235
Fair Value, Recurring
Assets:
Equity and other securities	225	235
Total assets	255	324
Liabilities:
Total liabilities	(5)	(3)
Fair Value, Recurring | Interest rate derivatives - cash flow hedges | Cash Flow Hedging
Assets:
Derivative assets	29	41
Liabilities:
Derivative liabilities	(4)	0
Fair Value, Recurring | Foreign currency derivatives - cash flow hedges | Cash Flow Hedging
Assets:
Derivative assets	1	2
Fair Value, Recurring | Cross currency interest rate derivatives
Assets:
Derivative assets	0	37
Liabilities:
Derivative liabilities	0	(2)
Fair Value, Recurring | Cross currency interest rate derivatives | Cash Flow Hedging
Liabilities:
Derivative liabilities	(1)	0
Fair Value, Recurring | Cross currency interest rate derivatives | Fair Value Hedging
Assets:
Derivative assets	0	9
Liabilities:
Derivative liabilities	0	(1)
Fair Value, Recurring | Level 1
Assets:
Equity and other securities	93	105
Total assets	93	105
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
Assets:
Derivative assets	0	0
Fair Value, Recurring | Level 1 | Cross currency interest rate derivatives
Assets:
Derivative assets	0	0
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 1 | Cross currency interest rate derivatives | Fair Value Hedging
Assets:
Derivative assets	0	0
Liabilities:
Derivative liabilities	0	0
Fair Value, Recurring | Level 2
Assets:
Equity and other securities	0	0
Total assets	30	89
Liabilities:
Total liabilities	(5)	(3)
Fair Value, Recurring | Level 2 | Interest rate derivatives - cash flow hedges | Cash Flow Hedging
Assets:
Derivative assets	29	41
Liabilities:
Derivative liabilities	(4)	0
Fair Value, Recurring | Level 2 | Foreign currency derivatives - cash flow hedges | Cash Flow Hedging
Assets:
Derivative assets	1	2
Fair Value, Recurring | Level 2 | Cross currency interest rate derivatives
Assets:
Derivative assets	0	37
Liabilities:
Derivative liabilities	0	(2)
Fair Value, Recurring | Level 2 | Cross currency interest rate derivatives | Cash Flow Hedging
Liabilities:
Derivative liabilities	(1)	0
Fair Value, Recurring | Level 2 | Cross currency interest rate derivatives | Fair Value Hedging
Assets:
Derivative assets	0	9
Liabilities:
Derivative liabilities	0	(1)
Fair Value, Recurring | Level 3
Assets:
Equity and other securities	132	130
Total assets	132	130
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
Assets:
Derivative assets	0	0
Fair Value, Recurring | Level 3 | Cross currency interest rate derivatives
Assets:
Derivative assets	0	0
Liabilities:
Derivative liabilities	0	0
Fair Value, Recurring | Level 3 | Cross currency interest rate derivatives | Cash Flow Hedging
Liabilities:
Derivative liabilities	0	0
Fair Value, Recurring | Level 3 | Cross currency interest rate derivatives | Fair Value Hedging
Assets:
Derivative assets	0	0
Liabilities:
Derivative liabilities	$ 0	$ 0