Schedule II (Details) - Condensed Statement of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Condensed Statement of Cash Flows
Net income	$ 3,662	$ 2,697	$ 2,622
Deferred federal income tax expense (benefit)	62	(29)	(33)
Other operating activities	750	129	535
Net cash provided by operating activities	7,274	6,519	5,205
Net sales (purchases) of short-term securities	1,671	(566)	(957)
Net cash used in investing activities	(5,196)	(4,892)	(2,902)
Treasury stock acquired — share repurchase authorization	(2,156)	(625)	(1,500)
Treasury stock acquired — net employee share-based compensation	(44)	(47)	(48)
Dividends paid to shareholders	(869)	(861)	(844)
Payment of debt	0	(500)	(500)
Issuance of debt	739	490	492
Issuance of common stock -- employee share options	293	127	213
Net cash used in financing activities	(2,037)	(1,416)	(2,187)
Net increase in cash	40	227	121
Cash at beginning of year	721	494	373
Cash at end of year	761	721	494
Cash received during the year for taxes	(707)	(578)	(428)
Cash paid during the year for interest	337	339	338
Travelers [Member]
Condensed Statement of Cash Flows
Net income	3,662	2,697	2,622
Equity in net income of subsidiaries	(3,867)	(2,900)	(2,789)
Dividends received from consolidated subsidiaries	2,149	1,964	2,459
Deferred federal income tax expense (benefit)	7	3	(2)
Change in income taxes payable	0	(6)	3
Other operating activities	(69)	(79)	(79)
Net cash provided by operating activities	1,882	1,679	2,214
Net sales (purchases) of short-term securities	167	(256)	(19)
Other investments, net	(11)	(7)	(8)
Net cash used in investing activities	156	(263)	(27)
Treasury stock acquired — share repurchase authorization	(2,156)	(625)	(1,500)
Treasury stock acquired — net employee share-based compensation	(44)	(47)	(48)
Dividends paid to shareholders	(869)	(861)	(844)
Payment of debt	0	(500)	(500)
Issuance of debt	739	490	492
Issuance of common stock -- employee share options	293	127	213
Net cash used in financing activities	(2,037)	(1,416)	(2,187)
Net increase in cash	1	0	0
Cash at beginning of year	0	0	0
Cash at end of year	1	0	0
Cash received during the year for taxes	66	81	78
Cash paid during the year for interest	$ 289	$ 291	$ 291