Schedule II (details) - Condensed Statement of Cash Flows (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Condensed financial statements
Net income	$ 2,473	$ 1,426	$ 3,216
Deferred federal income tax (benefit) expense	223	63	178
Other operating activities	206	(387)	53
Net cash provided by operating activities	3,230	2,169	3,054
Net sales (purchases) of short-term securities	117	2,018	(699)
Net cash provided by (used in) investing activities	(972)	1,152	2,109
Payment of debt	(258)	(8)	(1,160)
Issuance of debt			1,234
Dividends paid to shareholders	(694)	(665)	(673)
Issuance of common stock - employee share options	295	314	408
Treasury stock acquired - share repurchase authorization	(1,474)	(2,919)	(4,998)
Treasury stock acquired - net employee share-based compensation	(53)	(46)	(40)
Net cash used in financing activities	(2,146)	(3,306)	(5,221)
Net increase (decrease) in cash	116	14	(55)
Cash at beginning of year	214	200	255
Cash at end of year	330	214	200
Cash received during the year for taxes	(188)	(218)	(784)
Cash paid during the year for interest	375	382	397
Travelers [Member]
Condensed financial statements
Net income	2,473	1,426	3,216
Equity in net income of subsidiaries	(2,655)	(1,564)	(3,497)
Dividends received from consolidated subsidiaries	1,920	2,300	6,676
Capital (contributed to) repaid from subsidiaries		(10)	19
Deferred federal income tax (benefit) expense	52	43	(46)
Change in income taxes payable	(1)	(162)	63
Other operating activities	(16)	28	411
Net cash provided by operating activities	1,773	2,061	6,842
Net sales (purchases) of short-term securities	381	1,276	(1,723)
Other investments, net	(8)	(41)	99
Net cash provided by (used in) investing activities	373	1,235	(1,624)
Payment of debt	(258)		(1,156)
Issuance of debt			1,234
Dividends paid to shareholders	(694)	(665)	(673)
Issuance of common stock - employee share options	295	314	408
Treasury stock acquired - share repurchase authorization	(1,474)	(2,919)	(4,998)
Treasury stock acquired - net employee share-based compensation	(53)	(46)	(40)
Other financing activities	38	18	10
Net cash used in financing activities	(2,146)	(3,298)	(5,215)
Net increase (decrease) in cash		(2)	3
Cash at beginning of year	2	4	1
Cash at end of year	2	2	4
Cash received during the year for taxes	207	97	116
Cash paid during the year for interest	$ 302	$ 309	$ 324