Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	12 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2022
Statement of Comprehensive Income [Abstract]
Foreign currency translation, tax (benefit)/expense	$ 66	$ (197)	$ 515
Unrealized gains/(losses) on investment securities, tax (benefit)/expense	(1)	(2)	1
Unrealized gains/(losses) on defined benefit postretirement plans, tax expense	$ 230	$ 9	$ 1,022

Amount, after reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income of defined benefit plan.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
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