Segments of Business - Reportable operating segment (Details) $ in Millions	3 Months Ended
Jun. 30, 2022 USD ($) segment	Jun. 30, 2021 USD ($)
Segment revenues
Total revenues	$ 67,154	$ 62,674
Segment operating profit (loss)
Total operating profit (loss)	1,036	568
Corporate income (expenses), net	(39)	(303)
Interest expense	(45)	(49)
Income from continuing operations before income taxes	$ 1,006	562
Number of reportable segments \| segment	4
Pre-tax credits related to LIFO accounting	$ (13)	(23)
Gain to remeasure disposal group to fair value	$ 20	0
United States
Segment operating profit (loss)
Number of reportable segments \| segment	3
Held-for-sale \| E.U. Businesses (Disposal Group)
Segment operating profit (loss)
Gain to remeasure disposal group to fair value	$ (12)
Operating Segments
Segment operating profit (loss)
Total operating profit (loss)	1,090	914
Corporate \| National Prescription Opioid Litigation
Segment operating profit (loss)
Pre-tax expenses related to estimated litigation liability	5	74
Corporate \| Held-for-sale \| E.U. Businesses (Disposal Group)
Segment operating profit (loss)
Gain to remeasure disposal group to fair value	(106)
National Prescription Opioid Litigation \| Corporate
Segment operating profit (loss)
Litigation expense	19	35
U.S. Pharmaceutical
Segment revenues
Total revenues	56,947	50,019
U.S. Pharmaceutical \| Operating Segments
Segment operating profit (loss)
Total operating profit (loss)	$ 696	682
Revenue derived from services, percentage (less than)	1.00%
Pre-tax credits related to LIFO accounting	$ (13)	(23)
Prescription Technology Solutions
Segment revenues
Total revenues	1,066	881
Prescription Technology Solutions \| Operating Segments
Segment operating profit (loss)
Total operating profit (loss)	$ 144	104
Revenue derived from services, percentage (less than)	35.00%
Medical-Surgical Solutions
Segment revenues
Total revenues	$ 2,592	2,528
Medical-Surgical Solutions \| Operating Segments
Segment operating profit (loss)
Total operating profit (loss)	$ 256	75
Revenue derived from services, percentage (less than)	1.00%
Inventory charges		164
International
Segment revenues
Total revenues	$ 6,549	9,246
International \| Operating Segments
Segment operating profit (loss)
Total operating profit (loss)	$ (6)	$ 53
Revenue derived from services, percentage (less than)	8.00%
International \| Operating Segments \| Held-for-sale \| E.U. Businesses (Disposal Group)
Segment operating profit (loss)
Gain to remeasure disposal group to fair value	$ 94

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