Consolidated Statements of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022		Mar. 31, 2021
Cash flows from operating activities:
Net earnings	$ 5,585		$ 11,840
Adjustments to reconcile net earnings to operating cash flows:
Investment (gains) losses	1,735		(5,211)
Depreciation and amortization	2,703		2,673
Other	(961)		(225)
Changes in operating assets and liabilities:
Unpaid losses and loss adjustment expenses	558		961
Deferred charges - retroactive reinsurance	215		252
Unearned premiums	1,912		2,390
Receivables and originated loans	(3,469)		(3,440)
Other assets	(2,168)		(397)
Other liabilities	(85)		(1,861)
Income taxes	804		2,324
Net cash flows from operating activities	6,829		9,306
Cash flows from investing activities:
Purchases of equity securities	(51,119)		(2,572)
Sales of equity securities	9,724		6,451
Purchases of U.S. Treasury Bills and fixed maturity securities	(58,746)		(32,313)
Sales of U.S. Treasury Bills and fixed maturity securities	37,795		4,090
Redemptions and maturities of U.S. Treasury Bills and fixed maturity securities	6,571		37,559
Purchases of loans and finance receivables	(12)		(11)
Collections of loans and finance receivables	73		109
Acquisitions of businesses, net of cash acquired	(34)		(47)
Purchases of property, plant and equipment and equipment held for lease	(3,090)		(2,519)
Other	272		449
Net cash flows from investing activities	(58,566)		11,196
Cash flows from financing activities:
Changes in short term borrowings, net	(183)		229
Acquisition of treasury stock	(3,180)		(6,580)
Other	(367)		(132)
Net cash flows from financing activities	2,643		(8,349)
Effects of foreign currency exchange rate changes	50		(61)
Increase (decrease) in cash and cash equivalents and restricted cash	(49,044)		12,092
Cash and cash equivalents and restricted cash at beginning of year*	88,706		48,396
Cash and cash equivalents and restricted cash at end of first quarter*	39,662		60,488
Restricted cash, included in other assets at beginning of year	522		406
Restricted cash, included in other assets at end of first quarter	$ 549		$ 434
Restricted Cash and Cash Equivalents, Asset, Statement of Financial Position [Extensible List]	Other		Other
Insurance and Other [Member]
Cash flows from financing activities:
Proceeds from borrowings	$ 6,977		$ 1,442
Repayments of borrowings	(614)		(2,425)
Cash and cash equivalents at beginning of year	85,319	[1]	44,714
Cash and cash equivalents at end of first quarter	35,542	[1]	56,826
Railroad, Utilities and Energy [Member]
Cash flows from financing activities:
Proceeds from borrowings	405
Repayments of borrowings	(395)		(883)
Cash and cash equivalents at beginning of year	2,865	[1]	3,276
Cash and cash equivalents at end of first quarter	$ 3,571	[1]	$ 3,228

[1] Includes U.S. Treasury Bills with maturities of three months or less when purchased of $7.3 billion at March 31, 2022 and $61.7 billion at December 31, 2021.