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Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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Business Acquisitions and Divestitures - Narrative (Details) - USD ($) $ in Millions				3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 02, 2025	Apr. 01, 2025	Dec. 30, 2024	Jun. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Mar. 31, 2025
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Goodwill						$ 11,283		$ 10,022
Canadian businesses held for sale						0	$ 638
Held-for-sale \| Norway Disposal Group
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Divested net assets						112
Accumulated other comprehensive loss in charge for remeasurement to fair value						$ 171
Disposed of by sale \| Canadian retail disposal group
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Divested net assets			$ 741
Accumulated other comprehensive loss in charge for remeasurement to fair value								48
Cash proceeds from divestiture			9
Noncash divestiture, amount of consideration received			$ 120
Noncash divestiture payable period (in years)			6 years
Trade accounts payable			$ 125
Canadian businesses held for sale					$ 643		$ 643	$ 667
PRISM Vision LLC
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Controlling interest acquired (as a percent)		80.00%
Cash payments to acquire business		$ 871
Redeemable noncontrolling interests		25
Intangible assets		510
Goodwill		$ 429
PRISM Vision LLC \| Redeemable Noncontrolling Interests
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Redeemable noncontrolling interests				$ 25
PRISM Vision LLC \| PRISM Vision Physicians
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Ownership retained (as a percent)		20.00%
Core Ventures
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Controlling interest acquired (as a percent)	70.00%
Cash payments to acquire business	$ 2,481
Redeemable noncontrolling interests	700
Intangible assets	2,310
Goodwill	$ 785
Core Ventures \| Redeemable Noncontrolling Interests
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Redeemable noncontrolling interests				$ 700
Core Ventures \| FCS Physicians
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Ownership retained (as a percent)	30.00%
Exercisable term (in years)	5 years
Initial fair value (as a percent)	75.00%