Consolidating Financial Statements (details) - Consolidating Balance Sheet (Unaudited) - USD ($) shares in Millions, $ in Millions	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014	Dec. 31, 2013
Consolidating Balance Sheet
Fixed maturities, available for sale, at fair value	$ 61,933	$ 63,474
Equity securities, available for sale, at fair value	828	899
Real estate investments	980	938
Short-term securities	3,924	4,364
Other investments	3,565	3,586
Total investments	71,230	73,261
Cash	317	374	$ 311	$ 294
Investment income accrued	655	685
Premiums receivable	6,764	6,298
Reinsurance recoverables	8,965	9,260
Ceded unearned premiums	782	678
Deferred acquisition costs	1,891	1,835
Deferred taxes	216	33
Contractholder receivables	4,473	4,362
Goodwill	3,594	3,611
Other intangible assets	284	304
Other assets	2,493	2,377
Total assets	101,664	103,078
Claims and claim adjustment expense reserves	48,833	49,850
Unearned premium reserves	12,153	11,839
Contractholder payables	4,473	4,362
Payables for reinsurance premiums	428	336
Debt	6,350	6,349
Other liabilities	5,306	5,506
Total liabilities	77,543	78,242
Common stock	22,039	21,843	21,694	21,500
Retained earnings	28,524	27,251	25,662	24,291
Accumulated other comprehensive income	169	880	1,562	810
Treasury stock, at cost	(26,611)	(25,138)	(23,386)	$ (21,805)
Total shareholders' equity	24,121	24,836	$ 25,532
Total liabilities and shareholders' equity	101,664	103,078
Fixed maturities, available for sale, amortized cost	60,103	60,801
Equity securities, available for sale, cost	$ 573	$ 579
Common stock, shares authorized	1,750.0	1,750.0
Common stock, shares issued	311.2	322.2
Common stock, shares outstanding	311.2	322.2	339.0	353.5
Treasury stock, at cost, shares	451.5	437.3
Reportable Legal Entities [Member] | TPC [Member]
Consolidating Balance Sheet
Fixed maturities, available for sale, at fair value	$ 42,549	$ 43,401
Equity securities, available for sale, at fair value	224	236
Real estate investments	56	56
Short-term securities	1,798	2,128
Other investments	2,628	2,630
Total investments	47,255	48,451
Cash	184	221	$ 167	$ 137
Investment income accrued	451	468
Premiums receivable	4,504	4,241
Reinsurance recoverables	5,721	6,156
Ceded unearned premiums	690	608
Deferred acquisition costs	1,672	1,622
Deferred taxes	117	23
Contractholder receivables	3,417	3,306
Goodwill	2,589	2,602
Other intangible assets	202	216
Other assets	2,170	1,931
Total assets	68,972	69,845
Claims and claim adjustment expense reserves	32,161	32,999
Unearned premium reserves	8,414	8,201
Contractholder payables	3,417	3,306
Payables for reinsurance premiums	243	194
Debt	692	692
Other liabilities	4,145	4,084
Total liabilities	49,072	49,476
Additional paid-in capital	11,634	11,634
Retained earnings	7,711	7,673
Accumulated other comprehensive income	555	1,062
Total shareholders' equity	19,900	20,369
Total liabilities and shareholders' equity	68,972	69,845
Reportable Legal Entities [Member] | Other Subsidiaries [Member]
Consolidating Balance Sheet
Fixed maturities, available for sale, at fair value	19,340	20,043
Equity securities, available for sale, at fair value	460	522
Real estate investments	924	882
Short-term securities	478	706
Other investments	936	955
Total investments	22,138	23,108
Cash	131	151	143	154
Investment income accrued	201	215
Premiums receivable	2,260	2,057
Reinsurance recoverables	3,244	3,104
Ceded unearned premiums	92	70
Deferred acquisition costs	219	213
Deferred taxes	55	(40)
Contractholder receivables	1,056	1,056
Goodwill	1,005	1,009
Other intangible assets	82	88
Other assets	(32)	429
Total assets	30,451	31,460
Claims and claim adjustment expense reserves	16,672	16,851
Unearned premium reserves	3,739	3,638
Contractholder payables	1,056	1,056
Payables for reinsurance premiums	185	142
Other liabilities	630	1,308
Total liabilities	22,282	22,995
Common stock	390	390
Additional paid-in capital	6,502	6,502
Retained earnings	1,012	1,073
Accumulated other comprehensive income	265	500
Total shareholders' equity	8,169	8,465
Total liabilities and shareholders' equity	30,451	31,460
Reportable Legal Entities [Member] | Travelers [Member]
Consolidating Balance Sheet
Fixed maturities, available for sale, at fair value	44	30
Equity securities, available for sale, at fair value	144	141
Short-term securities	1,648	1,530
Other investments	1	1
Total investments	1,837	1,702
Cash	2	2	$ 1	$ 3
Investment income accrued	3	2
Deferred taxes	44	50
Investment in subsidiaries	28,057	28,821
Other assets	355	17
Total assets	30,298	30,594
Debt	5,658	5,657
Other liabilities	531	114
Total liabilities	6,189	5,771
Common stock	22,039	21,843
Retained earnings	28,512	27,238
Accumulated other comprehensive income	169	880
Treasury stock, at cost	(26,611)	(25,138)
Total shareholders' equity	24,109	24,823
Total liabilities and shareholders' equity	30,298	30,594
Eliminations [Member]
Consolidating Balance Sheet
Investment in subsidiaries	(28,057)	(28,821)
Total assets	(28,057)	(28,821)
Common stock	(390)	(390)
Additional paid-in capital	(18,136)	(18,136)
Retained earnings	(8,711)	(8,733)
Accumulated other comprehensive income	(820)	(1,562)
Total shareholders' equity	(28,057)	(28,821)
Total liabilities and shareholders' equity	$ (28,057)	$ (28,821)