Consolidated Statements of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018		Dec. 31, 2017		Dec. 31, 2016
Cash flows from operating activities:
Net earnings	$ 4,322		$ 45,353		$ 24,427
Adjustments to reconcile net earnings to operating cash flows:
Investment gains/losses	22,155		(1,410)		(7,553)
Depreciation and amortization	9,779		9,188		8,901
Other	2,957		458		(161)
Changes in operating assets and liabilities:
Losses and loss adjustment expenses	3,449		25,027		4,372
Deferred charges reinsurance assumed	1,174		(7,231)		(360)
Unearned premiums	1,794		1,761		968
Receivables and originated loans	(3,443)		(1,990)		(3,302)
Other assets	(1,832)		(1,665)		(373)
Other liabilities	2,002		1,194		1,684
Income taxes	(4,957)		(24,957)		4,044
Net cash flows from operating activities	37,400		45,728		32,647
Cash flows from investing activities:
Purchases of U.S. Treasury Bills and fixed maturity securities	(141,844)		(158,492)		(96,568)
Purchases of equity securities	(43,210)		(20,326)		(16,508)
Sales of U.S. Treasury Bills and fixed maturity securities	39,693		49,327		18,757
Redemptions and maturities of U.S. Treasury Bills and fixed maturity securities	113,045		86,727		26,177
Sales and redemptions of equity securities	18,783		19,512		28,464
Purchases of loans and finance receivables	(1,771)		(1,435)		(307)
Collections of loans and finance receivables	342		1,702		490
Acquisitions of businesses, net of cash acquired	(3,279)		(2,708)		(31,399)
Purchases of property, plant and equipment and equipment held for lease	(14,537)		(11,708)		(12,954)
Other	(71)		(3,608)		(377)
Net cash flows from investing activities	(32,849)		(41,009)		(84,225)
Cash flows from financing activities:
Changes in short term borrowings, net	(1,943)		2,079		130
Acquisition of treasury stock	(1,346)
Other	(343)		(121)		112
Net cash flows from financing activities	(5,812)		(1,398)		12,791
Effects of foreign currency exchange rate changes	(140)		248		(172)
Increase (decrease) in cash and cash equivalents and restricted cash	(1,401)		3,569		(38,959)
Cash and cash equivalents and restricted cash at beginning of year	32,212		28,643		67,602
Cash and cash equivalents and restricted cash at end of year	30,811		32,212		28,643
Restricted cash, included in other assets at end of year	450		629		595
Insurance and Other [Member]
Cash flows from financing activities:
Proceeds from borrowings	2,409		2,645		14,172
Repayments of borrowings	(7,395)		(5,465)		(2,577)
Cash and cash equivalents at end of year	27,749	[1]	28,673	[1]	24,109
Railroad, Utilities and Energy [Member]
Cash flows from financing activities:
Proceeds from borrowings	7,019		3,013		3,077
Repayments of borrowings	(4,213)		(3,549)		(2,123)
Cash and cash equivalents at end of year	$ 2,612	[1]	$ 2,910	[1]	$ 3,939

[1] Cash and cash equivalents includes U.S. Treasury Bills with maturities of three months or less when purchased of $3.9 billion at December 31, 2018 and $5.7 billion at December 31, 2017.