Accumulated other comprehensive income (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	$ 506,199
Other comprehensive income	(3,051)	$ 99	$ 905
Reclassifications into net earnings	487	117	95
Ending Balance	472,360	506,199
Unrealized gains (losses) on investments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	369	536	481
Other comprehensive income	(991)	(123)	78
Reclassifications into net earnings	435	(44)	(23)
Ending Balance	(187)	369	536
Foreign currency translation [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(4,092)	(3,082)	(4,346)
Other comprehensive income	(2,045)	(1,021)	1,264
Reclassifications into net earnings	(3)	11
Ending Balance	(6,140)	(4,092)	(3,082)
Defined benefit pension plans [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(347)	(1,645)	(1,369)
Other comprehensive income	(298)	1,163	(385)
Reclassifications into net earnings	93	135	109
Ending Balance	(552)	(347)	(1,645)
Other AOCI transactions [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(43)	(52)	9
Other comprehensive income	283	80	(52)
Reclassifications into net earnings	(38)	15	9
Ending Balance	288	(43)	(52)
Accumulated other comprehensive income [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(4,027)	(4,243)	(5,243)
Ending Balance	$ (6,591)	$ (4,027)	$ (4,243)