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Revenue Derived From Services, Percentage

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Amount, before tax, of (gain) loss recognized for the (reversal of write-down) write-down to fair value, less cost to sell, of a disposal group. Excludes discontinued operations.

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Amount of unrealized and realized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

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Amount of gain (loss) recognized in settlement of litigation and insurance claims. Excludes claims within an insurance entity's normal claims settlement process.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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Amount of the cost of borrowed funds accounted for as interest expense.

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The change in the inventory reserve representing the cumulative difference in cost between the first in, first out and the last in, first out inventory valuation methods, which change has been reflected in the statement of income during the period.

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Amount of loss from reductions in inventory due to subsequent measurement adjustments, including, but not limited to, physical deterioration, obsolescence, or changes in price levels.

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Amount of litigation expense, including but not limited to legal, forensic, accounting, and investigative fees.

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Amount of increase (decrease) in loss contingency liability.

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Amount charged against operating income increasing loss contingency liability, after adjustments to reduce previously estimated charges.

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The net result for the period of deducting operating expenses from operating revenues.

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Cash received for the settlement of litigation during the current period.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Segments of Business - Reportable operating segment (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Mar. 31, 2021
Segment revenues
Total revenues	$ 66,576	$ 60,808	$ 129,250	$ 116,487
Segment operating profit (loss)
Total operating profit (loss)	539	634	1,107	1,312
Corporate income (expenses), net	(360)	(148)	(663)	(216)
Loss on debt extinguishment	(191)	0	(191)	0
Interest expense	(45)	(50)	(94)	(110)
Income from continuing operations before income taxes	442	655	1,004	1,300
Pre-tax credits related to LIFO accounting			(46)	(104)
Charge for remeasurement to fair value			470	0
Restructuring, impairment, and related charges	32	60	190	116
Goodwill impairment charge	0	69	0	69
Net gain on settlement proceeds	(112)	0	(186)	131
European Businesses (Disposal Group)
Segment operating profit (loss)
Charge for remeasurement to fair value			491
National Prescription Opioid Litigation
Segment operating profit (loss)
Pre-tax expenses related to estimated litigation liability	112		186		$ 8,100
Held-for-sale
Segment operating profit (loss)
Loss on debt extinguishment	(191)		(191)
Held-for-sale \| European Businesses (Disposal Group)
Segment operating profit (loss)
Charge for remeasurement to fair value	491		491
Operating Segments
Segment operating profit (loss)
Total operating profit (loss)	1,038	853	1,952	1,626
Corporate
Segment operating profit (loss)
Restructuring, impairment, and related charges	19	12	81	40
Gains associated with equity investments	97	49	104	59
Corporate \| National Prescription Opioid Litigation
Segment operating profit (loss)
Pre-tax expenses related to estimated litigation liability	112		186
Corporate \| Held-for-sale \| European Businesses (Disposal Group)
Segment operating profit (loss)
Charge for remeasurement to fair value	149		149
National Prescription Opioid Litigation \| Corporate
Segment operating profit (loss)
Litigation expense	36	41	71	84
Shareholder derivative action \| Corporate
Segment operating profit (loss)
Net gain on settlement proceeds				131
U.S. Pharmaceutical
Segment revenues
Total revenues	53,411	48,067	103,430	92,737
U.S. Pharmaceutical \| Operating Segments
Segment operating profit (loss)
Total operating profit (loss)	760	623	$ 1,442	1,236
Revenue derived from services, percentage (less than)			1.00%
Pre-tax credits related to LIFO accounting	23	52	$ 46	104
Restructuring, impairment, and related charges	10	10	22	12
U.S. Pharmaceutical \| Operating Segments \| New York Opioid Tax Surcharge
Segment operating profit (loss)
Charge recorded related to Company's share of the litigation settlement		50		50
U.S. Pharmaceutical \| Antitrust Legal Settlements \| Operating Segments
Segment operating profit (loss)
Company's shares of legal settlements	34		46
Prescription Technology Solutions
Segment revenues
Total revenues	932	668	1,813	1,324
Prescription Technology Solutions \| Operating Segments
Segment operating profit (loss)
Total operating profit (loss)	128	88	$ 232	156
Revenue derived from services, percentage (less than)			40.00%
Restructuring, impairment, and related charges	0	0	$ 18	0
Medical-Surgical Solutions
Segment revenues
Total revenues	3,124	2,533	5,652	4,334
Medical-Surgical Solutions \| Operating Segments
Segment operating profit (loss)
Total operating profit (loss)	296	187	$ 371	276
Revenue derived from services, percentage (less than)			3.00%
Inventory impairments and excess inventory			$ 164
Restructuring, impairment, and related charges	2	3	8	6
International
Segment revenues
Total revenues	9,109	9,540	18,355	18,092
International \| Retail Pharmacy Reporting Unit
Segment operating profit (loss)
Goodwill impairment charge		69		69
International \| Operating Segments
Segment operating profit (loss)
Total operating profit (loss)	(146)	(45)	$ (93)	(42)
Revenue derived from services, percentage (less than)			8.00%
Charge for remeasurement to fair value	342		$ 342
Restructuring, impairment, and related charges	1	35	61	58
International \| Operating Segments \| Retail Pharmacy Reporting Unit
Segment operating profit (loss)
Goodwill impairment charge		$ 69		$ 69
International \| Operating Segments \| Disposed of by sale \| Canadian Health Benefit Claims Management and Plan Administrative Services Business
Segment operating profit (loss)
Pre-tax gain on sale of business	$ 59		$ 59