Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net earnings	$ 12,077	$ 4,355	$ 11,006	$ 8,494
Other comprehensive income:
Net change in unrealized appreciation of investments	(92)	4,711	(137)	13,088
Applicable income taxes	22	(1,659)	20	(4,531)
Reclassification of investment appreciation in net earnings	(44)	(284)	(265)	(589)
Applicable income taxes	10	99	56	206
Foreign currency translation	(1,364)	798	(763)	1,356
Applicable income taxes	43	(23)	37	(92)
Prior service cost and actuarial gains/losses of defined benefit pension plans	87	(44)	63	(54)
Applicable income taxes	(20)	18	(3)	25
Other, net	(5)	3	(36)	6
Other comprehensive income, net	(1,363)	3,619	(1,028)	9,415
Comprehensive income	10,714	7,974	9,978	17,909
Comprehensive income attributable to noncontrolling interests	34	130	109	233
Comprehensive income attributable to Berkshire Hathaway shareholders	$ 10,680	$ 7,844	$ 9,869	$ 17,676