Consolidated Statements of Shareholders' Equity - USD ($) $ in Millions		Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Treasury Stock
Balance, beginning of period at Dec. 31, 2022		$ 20,140	$ 135	$ 2,641	$ 44,367	$ (6,429)	$ (20,574)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings		1,188	0	0	1,188	0	0
Unrealized foreign currency translation gains (losses) during period, net of income taxes		(54)	0	0	0	(54)	0
Unrealized gains (losses) on fixed maturity securities during period, net of income taxes and reclassification adjustments		1,991	0	0	0	1,991	0
Unrealized gains (losses) on derivatives during period, net of income taxes		1	0	0	0	1	0
Effect of changes in discount rate assumptions during period, net of income taxes		(2,794)	0	0	0	(2,794)	0
Pension liability adjustment during period, net of income taxes		7	0	0	0	7	0
Dividends to shareholders	[1]	0	0	0	0	0	0
Exercise of stock options		3	0	3	0	0	0
Share-based compensation		14	0	14	0	0	0
Purchases of treasury stock		(732)	0	0	0	0	(732)
Treasury stock reissued		20	0	7	0	0	13
Balance, end of period at Mar. 31, 2023		19,784	135	2,665	45,555	(7,278)	(21,293)
Balance, beginning of period at Dec. 31, 2022		20,140	135	2,641	44,367	(6,429)	(20,574)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings		4,391
Effect of changes in discount rate assumptions during period, net of income taxes						1,200
Balance, end of period at Sep. 30, 2023		22,669	136	2,729	48,257	(5,760)	(22,693)
Balance, beginning of period at Dec. 31, 2022		20,140	135	2,641	44,367	(6,429)	(20,574)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Effect of changes in discount rate assumptions during period, net of income taxes						(460)
Balance, end of period at Dec. 31, 2023		21,985	136	2,771	47,993	(5,520)	(23,395)
Balance, beginning of period at Mar. 31, 2023		19,784	135	2,665	45,555	(7,278)	(21,293)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings		1,634	0	0	1,634	0	0
Unrealized foreign currency translation gains (losses) during period, net of income taxes		(631)	0	0	0	(631)	0
Unrealized gains (losses) on fixed maturity securities during period, net of income taxes and reclassification adjustments		689	0	0	0	689	0
Unrealized gains (losses) on derivatives during period, net of income taxes		1	0	0	0	1	0
Effect of changes in discount rate assumptions during period, net of income taxes		(165)	0	0	0	(165)	0
Pension liability adjustment during period, net of income taxes		46	0	0	0	46	0
Dividends to shareholders	[1]	(252)	0	0	(252)	0	0
Exercise of stock options		5	0	5	0	0	0
Share-based compensation		18	1	17	0	0	0
Purchases of treasury stock		(708)	0	0	0	0	(708)
Treasury stock reissued		18	0	10	0	0	8
Balance, end of period at Jun. 30, 2023		20,439	136	2,697	46,937	(7,338)	(21,993)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings		1,569	0	0	1,569	0	0
Unrealized foreign currency translation gains (losses) during period, net of income taxes		(235)	0	0	0	(235)	0
Unrealized gains (losses) on fixed maturity securities during period, net of income taxes and reclassification adjustments		(2,381)	0	0	0	(2,381)	0
Unrealized gains (losses) on derivatives during period, net of income taxes		1	0	0	0	1	0
Effect of changes in discount rate assumptions during period, net of income taxes		4,193	0	0	0	4,193	0
Pension liability adjustment during period, net of income taxes		0	0	0	0	0	0
Dividends to shareholders	[1]	(249)	0	0	(249)	0	0
Exercise of stock options		2	0	2	0	0	0
Share-based compensation		20	0	20	0	0	0
Purchases of treasury stock		(707)	0	0	0	0	(707)
Treasury stock reissued		17	0	10	0	0	7
Balance, end of period at Sep. 30, 2023		22,669	136	2,729	48,257	(5,760)	(22,693)
Balance, beginning of period at Dec. 31, 2023		21,985	136	2,771	47,993	(5,520)	(23,395)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings		1,879	0	0	1,879	0	0
Unrealized foreign currency translation gains (losses) during period, net of income taxes		(597)	0	0	0	(597)	0
Unrealized gains (losses) on fixed maturity securities during period, net of income taxes and reclassification adjustments		(47)	0	0	0	(47)	0
Unrealized gains (losses) on derivatives during period, net of income taxes		(4)	0	0	0	(4)	0
Effect of changes in discount rate assumptions during period, net of income taxes		1,065	0	0	0	1,065	0
Pension liability adjustment during period, net of income taxes		1	0	0	0	1	0
Dividends to shareholders	[1]	0	0	0	0	0	0
Exercise of stock options		4	0	4	0	0	0
Share-based compensation		18	0	18	0	0	0
Purchases of treasury stock		(793)	0	0	0	0	(793)
Treasury stock reissued		26	0	13	0	0	13
Balance, end of period at Mar. 31, 2024		23,537	136	2,806	49,872	(5,102)	(24,175)
Balance, beginning of period at Dec. 31, 2023		21,985	136	2,771	47,993	(5,520)	(23,395)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings		3,541
Effect of changes in discount rate assumptions during period, net of income taxes						2,500
Balance, end of period at Sep. 30, 2024		24,830	136	2,876	50,972	(3,677)	(25,477)
Balance, beginning of period at Mar. 31, 2024		23,537	136	2,806	49,872	(5,102)	(24,175)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings		1,755	0	0	1,755	0	0
Unrealized foreign currency translation gains (losses) during period, net of income taxes		(425)	0	0	0	(425)	0
Unrealized gains (losses) on fixed maturity securities during period, net of income taxes and reclassification adjustments		(691)	0	0	0	(691)	0
Unrealized gains (losses) on derivatives during period, net of income taxes		4	0	0	0	4	0
Effect of changes in discount rate assumptions during period, net of income taxes		2,920	0	0	0	2,920	0
Pension liability adjustment during period, net of income taxes		2	0	0	0	2	0
Dividends to shareholders	[1]	(282)	0	0	(282)	0	0
Exercise of stock options		2	0	2	0	0	0
Share-based compensation		12	0	12	0	0	0
Purchases of treasury stock		(810)	0	0	0	0	(810)
Treasury stock reissued		23	0	15	0	0	8
Balance, end of period at Jun. 30, 2024		26,047	136	2,835	51,345	(3,292)	(24,977)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings		(93)	0	0	(93)	0	0
Unrealized foreign currency translation gains (losses) during period, net of income taxes		952	0	0	0	952	0
Unrealized gains (losses) on fixed maturity securities during period, net of income taxes and reclassification adjustments		156	0	0	0	156	0
Unrealized gains (losses) on derivatives during period, net of income taxes		2	0	0	0	2	0
Effect of changes in discount rate assumptions during period, net of income taxes		(1,492)	0	0	0	(1,492)	0
Pension liability adjustment during period, net of income taxes		(3)	0	0	0	(3)	0
Dividends to shareholders	[1]	(280)	0	0	(280)	0	0
Exercise of stock options		1	0	1	0	0	0
Share-based compensation		21	0	21	0	0	0
Purchases of treasury stock		(505)	0	0	0	0	(505)
Treasury stock reissued		24	0	19	0	0	5
Balance, end of period at Sep. 30, 2024		$ 24,830	$ 136	$ 2,876	$ 50,972	$ (3,677)	$ (25,477)

[1] Dividends to shareholders are recorded in the period in which they are declared.