Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	12 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2023
Statement of Comprehensive Income [Abstract]
Foreign currency translation, tax (benefit)/expense	$ (442)	$ 66	$ (197)
Unrealized gains/(losses) on investment securities, tax (benefit)/expense	(1)	(1)	(2)
Unrealized gains/(losses) on defined benefit postretirement plans, tax expense	$ (407)	$ 230	$ 9

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
-Section 45
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-Subparagraph (j)
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-Publisher FASB
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
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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
-Topic 810
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Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
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