Schedule II (Details) - Condensed Statement of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Condensed Statement of Cash Flows
Net income	$ 2,842	$ 3,662	$ 2,697
Deferred federal income tax expense (benefit)	(186)	62	(29)
Other operating activities	45	750	129
Net cash provided by operating activities	6,465	7,274	6,519
Net sales (purchases) of short-term securities	355	1,671	(566)
Net cash used in investing activities	(3,728)	(5,196)	(4,892)
Treasury stock acquired — share repurchase authorization	(2,000)	(2,156)	(625)
Treasury stock acquired — net employee share-based compensation	(61)	(44)	(47)
Dividends paid to shareholders	(875)	(869)	(861)
Payment of debt	0	0	(500)
Issuance of debt	0	739	490
Issuance of common stock -- employee share options	267	293	127
Net cash used in financing activities	(2,669)	(2,037)	(1,416)
Net increase in cash	38	40	227
Cash at beginning of year	761	721	494
Cash at end of year	799	761	721
Cash received during the year for taxes	(817)	(707)	(578)
Cash paid during the year for interest	349	337	339
Travelers [Member]
Condensed Statement of Cash Flows
Net income	2,842	3,662	2,697
Equity in net income of subsidiaries	(3,080)	(3,867)	(2,900)
Dividends received from consolidated subsidiaries	2,860	2,149	1,964
Deferred federal income tax expense (benefit)	14	7	3
Change in income taxes payable	(13)	0	(6)
Other operating activities	7	(69)	(79)
Net cash provided by operating activities	2,630	1,882	1,679
Net sales (purchases) of short-term securities	73	167	(256)
Other investments, net	(35)	(11)	(7)
Net cash used in investing activities	38	156	(263)
Treasury stock acquired — share repurchase authorization	(2,000)	(2,156)	(625)
Treasury stock acquired — net employee share-based compensation	(61)	(44)	(47)
Dividends paid to shareholders	(875)	(869)	(861)
Payment of debt	0	0	(500)
Issuance of debt	0	739	490
Issuance of common stock -- employee share options	267	293	127
Net cash used in financing activities	(2,669)	(2,037)	(1,416)
Net increase in cash	(1)	1	0
Cash at beginning of year	1	0	0
Cash at end of year	0	1	0
Cash received during the year for taxes	100	66	81
Cash paid during the year for interest	$ 301	$ 289	$ 291