Consolidated Statements of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023		Mar. 31, 2022
Cash flows from operating activities:
Net earnings	$ 35,757		$ 5,705
Adjustments to reconcile net earnings to operating cash flows:
Investment (gains) losses	(34,758)		1,735
Depreciation and amortization	3,051		2,703
Other	(1,293)		(960)
Changes in operating assets and liabilities:
Unpaid losses and loss adjustment expenses	22		558
Deferred charges - retroactive reinsurance	172		215
Unearned premiums	1,686		1,912
Receivables and originated loans	(922)		(3,536)
Inventories	(15)		(1,842)
Other assets	(987)		(328)
Other liabilities	(2,649)		(165)
Income taxes	8,629		829
Net cash flows from operating activities	8,693		6,826
Cash flows from investing activities:
Purchases of equity securities	(2,873)		(51,119)
Sales of equity securities	13,283		9,724
Purchases of U.S. Treasury Bills and fixed maturity securities	(45,515)		(58,746)
Sales of U.S. Treasury Bills and fixed maturity securities	12,982		37,795
Redemptions and maturities of U.S. Treasury Bills and fixed maturity securities	25,364		6,571
Acquisitions of businesses, net of cash acquired	(7,629)		(34)
Purchases of property, plant and equipment and equipment held for lease	(3,713)		(3,090)
Other	182		333
Net cash flows from investing activities	(7,919)		(58,566)
Cash flows from financing activities:
Changes in short term borrowings, net	1,098		(183)
Acquisition of treasury stock	(4,450)		(3,180)
Other, principally transactions with noncontrolling interests	(380)		(367)
Net cash flows from financing activities	(9,922)		2,643
Effects of foreign currency exchange rate changes	47		53
Increase (decrease) in cash and cash equivalents and restricted cash	(9,101)		(49,044)
Cash and cash equivalents and restricted cash at beginning of year	36,399		88,706
Cash and cash equivalents and restricted cash at end of first quarter	27,298		39,662
Restricted cash, included in other assets at beginning of year	588		522
Restricted cash, included in other assets at end of first quarter	$ 551		$ 549
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
Repayments of borrowings	$ (4,946)		(614)
Cash and cash equivalents at beginning of year	32,260	[1]	85,319
Cash and cash equivalents at end of first quarter	23,805	[1]	35,542
Railroad, Utilities and Energy [Member]
Cash flows from financing activities:
Proceeds from borrowings			405
Repayments of borrowings	(1,244)		(395)
Cash and cash equivalents at beginning of year	3,551	[1]	2,865
Cash and cash equivalents at end of first quarter	$ 2,942	[1]	$ 3,571

[1] Includes U.S. Treasury Bills with maturities of three months or less when purchased of $3.6 billion at March 31, 2023 and $2.6 billion at December 31, 2022.