Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Statement Of Income And Comprehensive Income [Abstract]
Net earnings (loss)	$ (49,697)	$ 21,732
Other comprehensive income:
Unrealized appreciation of investments	(180)	122
Applicable income taxes	41	(28)
Foreign currency translation	(1,454)	183
Applicable income taxes	47	(3)
Defined benefit pension plans	95	66
Applicable income taxes	(21)	(17)
Other, net	(59)	(13)
Other comprehensive income, net	(1,531)	310
Comprehensive income	(51,228)	22,042
Comprehensive income attributable to noncontrolling interests	(4)	93
Comprehensive income attributable to Berkshire Hathaway shareholders	$ (51,224)	$ 21,949

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