Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Comprehensive Income [Abstract]
Net earnings	$ 4,322	$ 45,353	$ 24,427
Other comprehensive income:
Net change in unrealized appreciation of investments	(185)	30,450	13,858
Applicable income taxes	31	(10,566)	(4,846)
Reclassification of investment appreciation in net earnings	(253)	(1,399)	(6,820)
Applicable income taxes	53	490	2,387
Foreign currency translation	(1,531)	2,364	(1,541)
Applicable income taxes	62	(95)	66
Prior service cost and actuarial gains/losses of defined benefit pension plans	(571)	225	354
Applicable income taxes	143	(45)	(187)
Other, net	(12)	(9)	(17)
Other comprehensive income, net	(2,263)	21,415	3,254
Comprehensive income	2,059	66,768	27,681
Comprehensive income attributable to noncontrolling interests	249	555	291
Comprehensive income attributable to Berkshire Hathaway shareholders	$ 1,810	$ 66,213	$ 27,390