Supplemental cash flow information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Supplemental Cash Flow Information [Line Items]
Cash paid during the period for income taxes	$ 4,236	$ 5,412	$ 5,001
Other adjustments to reconcile net earnings to operating cash flows:
Foreign currency exchange (gains) losses	(2,148)	(1,433)	1,074
Goodwill and intangible asset impairment charges			10,671
Other	(2,176)	(1,964)	(482)
Non-cash investing and financing activities:
Liabilities assumed in connection with business acquisitions	24,186	102	6,981
Operating lease liabilities arising from obtaining right-of-use assets	1,118	687	729
Insurance and Other [Member]
Supplemental Cash Flow Information [Line Items]
Cash paid during the period for interest	1,150	1,227	1,001
Other adjustments to reconcile net earnings to operating cash flows:
Goodwill and intangible asset impairment charges			10,671
Railroad, Utilities and Energy [Member]
Supplemental Cash Flow Information [Line Items]
Cash paid during the period for interest	$ 3,195	$ 3,162	$ 3,006