Schedule II (Details) - Condensed Statement of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Condensed Statement of Comprehensive Income
Net income	$ 3,662	$ 2,697	$ 2,622
Changes in net unrealized gains (losses) on investment securities having no credit losses recognized in the consolidated statement of income	(2,115)	2,331	2,994
Net changes in benefit plan assets and obligations	455	18	33
Other comprehensive income (loss) before income taxes	(1,671)	2,352	3,140
Income tax expense (benefit)	(362)	490	641
Other comprehensive income (loss), net of taxes	(1,309)	1,862	2,499
Comprehensive income	2,353	4,559	5,121
Travelers [Member]
Condensed Statement of Comprehensive Income
Net income	3,662	2,697	2,622
Changes in net unrealized gains (losses) on investment securities having no credit losses recognized in the consolidated statement of income	(4)	3	4
Net changes in benefit plan assets and obligations	444	25	35
Other comprehensive income (loss) before income taxes	440	28	39
Income tax expense (benefit)	87	9	12
Other comprehensive income (loss), net of taxes, before other comprehensive income (loss) of subsidiaries	353	19	27
Other comprehensive income (loss) of subsidiaries	(1,662)	1,843	2,472
Other comprehensive income (loss), net of taxes	(1,309)	1,862	2,499
Comprehensive income	$ 2,353	$ 4,559	$ 5,121