Condensed Financial Information - Statements of Cash Flows (Detail) - USD ($)
$ in Millions |
3 Months Ended |
12 Months Ended |
Dec. 31, 2018 |
Sep. 30, 2018 |
[1] |
Jun. 30, 2018 |
[1] |
Mar. 31, 2018 |
Dec. 31, 2017 |
Sep. 30, 2017 |
[1] |
Jun. 30, 2017 |
[1] |
Mar. 31, 2017 |
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
| Cash flows from operating activities: |
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|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Net earnings attributable to Berkshire Hathaway shareholders |
$ (25,392)
|
[1] |
$ 18,540
|
$ 12,011
|
$ (1,138)
|
[1] |
$ 32,551
|
[1] |
$ 4,067
|
$ 4,262
|
$ 4,060
|
[1] |
$ 4,021
|
$ 44,940
|
$ 24,074
|
| Adjustments to reconcile net earnings to cash flows from operating activities: |
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|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Investment gains (losses) |
|
|
|
|
|
|
|
|
|
|
|
|
22,155
|
(1,410)
|
(7,553)
|
| Income taxes payable |
|
|
|
|
|
|
|
|
|
|
|
|
(4,957)
|
(24,957)
|
4,044
|
| Other |
|
|
|
|
|
|
|
|
|
|
|
|
2,957
|
458
|
(161)
|
| Net cash flows from operating activities |
|
|
|
|
|
|
|
|
|
|
|
|
37,400
|
45,728
|
32,647
|
| Cash flows from investing activities: |
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|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Net cash flows from investing activities |
|
|
|
|
|
|
|
|
|
|
|
|
(32,849)
|
(41,009)
|
(84,225)
|
| Cash flows from financing activities: |
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|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Acquisition of treasury stock |
|
|
|
|
|
|
|
|
|
|
|
|
(1,346)
|
|
|
| Other |
|
|
|
|
|
|
|
|
|
|
|
|
(343)
|
(121)
|
112
|
| Net cash flows from financing activities |
|
|
|
|
|
|
|
|
|
|
|
|
(5,812)
|
(1,398)
|
12,791
|
| Other cash flow information: |
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|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Income taxes paid |
|
|
|
|
|
|
|
|
|
|
|
|
4,354
|
3,286
|
4,719
|
| Berkshire Hathaway Inc. (Parent) [Member] |
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|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Cash flows from operating activities: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Net earnings attributable to Berkshire Hathaway shareholders |
|
|
|
|
|
|
|
|
|
|
|
|
4,021
|
44,940
|
24,074
|
| Adjustments to reconcile net earnings to cash flows from operating activities: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Investment gains (losses) |
|
|
|
|
|
|
|
|
|
|
|
|
4
|
1
|
(700)
|
| Undistributed earnings of consolidated subsidiaries |
|
|
|
|
|
|
|
|
|
|
|
|
3,952
|
(37,832)
|
(13,264)
|
| Income taxes payable |
|
|
|
|
|
|
|
|
|
|
|
|
(972)
|
(135)
|
629
|
| Other |
|
|
|
|
|
|
|
|
|
|
|
|
3,062
|
(1,234)
|
(161)
|
| Net cash flows from operating activities |
|
|
|
|
|
|
|
|
|
|
|
|
10,067
|
5,740
|
10,578
|
| Cash flows from investing activities: |
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|
|
|
|
|
|
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|
|
|
|
|
|
| Redemption of Kraft Heinz Company preferred stock |
|
|
|
|
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|
|
|
|
|
|
|
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|
8,320
|
| Investments in and advances to/from consolidated subsidiaries, net |
|
|
|
|
|
|
|
|
|
|
|
|
460
|
(239)
|
(26,398)
|
| Purchases of U.S. Treasury Bills |
|
|
|
|
|
|
|
|
|
|
|
|
(29,740)
|
(19,663)
|
(9,350)
|
| Sales and maturities of U.S. Treasury Bills |
|
|
|
|
|
|
|
|
|
|
|
|
21,442
|
14,847
|
1,145
|
| Net cash flows from investing activities |
|
|
|
|
|
|
|
|
|
|
|
|
(7,838)
|
(5,055)
|
(26,283)
|
| Cash flows from financing activities: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Proceeds from borrowings |
|
|
|
|
|
|
|
|
|
|
|
|
17
|
1,201
|
9,278
|
| Repayments of borrowings |
|
|
|
|
|
|
|
|
|
|
|
|
(1,563)
|
(1,145)
|
(1,125)
|
| Acquisition of treasury stock |
|
|
|
|
|
|
|
|
|
|
|
|
(1,346)
|
|
|
| Other |
|
|
|
|
|
|
|
|
|
|
|
|
61
|
77
|
164
|
| Net cash flows from financing activities |
|
|
|
|
|
|
|
|
|
|
|
|
(2,831)
|
133
|
8,317
|
| Increase (decrease) in cash and cash equivalents |
|
|
|
|
|
|
|
|
|
|
|
|
(602)
|
818
|
(7,388)
|
| Cash and cash equivalents at beginning of year |
|
|
|
|
$ 4,039
|
|
|
|
|
|
$ 3,221
|
|
4,039
|
3,221
|
10,609
|
| Cash and cash equivalents at end of year |
$ 3,437
|
|
|
|
|
|
$ 4,039
|
|
|
|
|
|
3,437
|
4,039
|
3,221
|
| Other cash flow information: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Income taxes paid |
|
|
|
|
|
|
|
|
|
|
|
|
2,790
|
2,076
|
3,583
|
| Interest paid |
|
|
|
|
|
|
|
|
|
|
|
|
$ 388
|
$ 386
|
$ 307
|
|
|