Schedule II (details) - Condensed Balance Sheet (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Condensed financial statements
Fixed maturities, available for sale, at fair value	$ 65,393	$ 64,232
Equity securities, available for sale, at fair value	645	559
Short-term securities	3,483	3,594
Total assets	104,938	104,575
Debt	6,350	6,605
Total liabilities	79,533	80,098
Common stock (1,750.0 shares authorized; 377.4 and 392.8 shares issued and outstanding)	21,161	20,732	20,162	19,593
Retained earnings	21,352	19,579	18,847	16,315
Accumulated other comprehensive income	2,236	2,005	1,255	1,219
Treasury stock, at cost (372.3 and 349.0 shares)	(19,344)	(17,839)	(14,857)	(9,791)
Total shareholders' equity	25,405	24,477	25,475
Total liabilities and shareholders' equity	104,938	104,575
Common stock, shares authorized	1,750.0	1,750.0
Common stock, shares issued	377.4	392.8
Common stock, shares outstanding	377.4	392.8	434.6	520.3
Treasury stock, at cost, shares	372.3	349.0
Travelers [Member]
Condensed financial statements
Fixed maturities, available for sale, at fair value	38	33
Equity securities, available for sale, at fair value	106	94
Short-term securities	1,958	2,339
Investment in subsidiaries	28,562	27,565
Other assets	26	506
Total assets	30,690	30,537
Debt	5,159	5,415
Other liabilities	136	655
Total liabilities	5,295	6,070
Common stock (1,750.0 shares authorized; 377.4 and 392.8 shares issued and outstanding)	21,161	20,732
Retained earnings	21,342	19,569
Accumulated other comprehensive income	2,236	2,005
Treasury stock, at cost (372.3 and 349.0 shares)	(19,344)	(17,839)
Total shareholders' equity	25,395	24,467
Total liabilities and shareholders' equity	$ 30,690	$ 30,537
Common stock, shares authorized	1,750.0	1,750.0
Common stock, shares issued	377.4	392.8
Common stock, shares outstanding	377.4	392.8
Treasury stock, at cost, shares	372.3	349.0