Consolidating Financial Statements (details) - Consolidating Balance Sheet (Unaudited) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013
Consolidating Balance Sheet
Fixed maturities, available for sale, at fair value	$ 62,769	$ 63,474
Equity securities, available for sale, at fair value	866	899
Real estate investments	929	938
Short-term securities	4,490	4,364
Other investments	3,565	3,586
Total investments	72,619	73,261
Cash	308	374	260	294
Investment income accrued	628	685
Premiums receivable	6,528	6,298
Reinsurance recoverables	9,142	9,260
Ceded unearned premiums	830	678
Deferred acquisition costs	1,847	1,835
Deferred taxes		33
Contractholder receivables	4,396	4,362
Goodwill	3,590	3,611
Other intangible assets	292	304
Other assets	2,511	2,377
Total assets	102,691	103,078
Claims and claim adjustment expense reserves	48,994	49,850
Unearned premium reserves	11,954	11,839
Contractholder payables	4,396	4,362
Payables for reinsurance premiums	485	336
Deferred taxes	126
Debt	6,349	6,349
Other liabilities	5,540	5,506
Total liabilities	77,844	78,242
Common stock	21,982	21,843	21,603	21,500
Retained earnings	27,906	27,251	25,167	24,291
Accumulated other comprehensive income	769	880	1,127	810
Treasury stock, at cost	(25,810)	(25,138)	(22,510)	(21,805)
Total shareholders' equity	24,847	24,836	25,387
Total liabilities and shareholders' equity	102,691	103,078
Fixed maturities, available for sale, amortized cost	59,916	60,801
Equity securities, available for sale, cost	563	579
Common stock, shares authorized	1,750.0	1,750.0
Common stock, shares issued	318.7	322.2
Common stock, shares outstanding	318.7	322.2	347.5	353.5
Treasury stock, at cost, shares	443.6	437.3
Reportable Legal Entities [Member] | TPC [Member]
Consolidating Balance Sheet
Fixed maturities, available for sale, at fair value	42,990	43,401
Equity securities, available for sale, at fair value	220	236
Real estate investments	56	56
Short-term securities	2,149	2,128
Other investments	2,627	2,630
Total investments	48,042	48,451
Cash	195	221	139	137
Investment income accrued	432	468
Premiums receivable	4,359	4,241
Reinsurance recoverables	6,093	6,156
Ceded unearned premiums	748	608
Deferred acquisition costs	1,636	1,622
Deferred taxes		23
Contractholder receivables	3,350	3,306
Goodwill	2,586	2,602
Other intangible assets	208	216
Other assets	2,082	1,931
Total assets	69,731	69,845
Claims and claim adjustment expense reserves	32,482	32,999
Unearned premium reserves	8,323	8,201
Contractholder payables	3,350	3,306
Payables for reinsurance premiums	287	194
Deferred taxes	114
Debt	692	692
Other liabilities	4,098	4,084
Total liabilities	49,346	49,476
Additional paid-in capital	11,634	11,634
Retained earnings	7,752	7,673
Accumulated other comprehensive income	999	1,062
Total shareholders' equity	20,385	20,369
Total liabilities and shareholders' equity	69,731	69,845
Reportable Legal Entities [Member] | Other Subsidiaries [Member]
Consolidating Balance Sheet
Fixed maturities, available for sale, at fair value	19,749	20,043
Equity securities, available for sale, at fair value	502	522
Real estate investments	873	882
Short-term securities	694	706
Other investments	937	955
Total investments	22,755	23,108
Cash	111	151	119	154
Investment income accrued	193	215
Premiums receivable	2,169	2,057
Reinsurance recoverables	3,049	3,104
Ceded unearned premiums	82	70
Deferred acquisition costs	211	213
Deferred taxes		(40)
Contractholder receivables	1,046	1,056
Goodwill	1,004	1,009
Other intangible assets	84	88
Other assets	413	429
Total assets	31,117	31,460
Claims and claim adjustment expense reserves	16,512	16,851
Unearned premium reserves	3,631	3,638
Contractholder payables	1,046	1,056
Payables for reinsurance premiums	198	142
Deferred taxes	63
Other liabilities	1,242	1,308
Total liabilities	22,692	22,995
Common stock	390	390
Additional paid-in capital	6,502	6,502
Retained earnings	1,098	1,073
Accumulated other comprehensive income	435	500
Total shareholders' equity	8,425	8,465
Total liabilities and shareholders' equity	31,117	31,460
Reportable Legal Entities [Member] | Travelers [Member]
Consolidating Balance Sheet
Fixed maturities, available for sale, at fair value	30	30
Equity securities, available for sale, at fair value	144	141
Short-term securities	1,647	1,530
Other investments	1	1
Total investments	1,822	1,702
Cash	2	2	2	3
Investment income accrued	3	2
Deferred taxes		50
Investment in subsidiaries	28,798	28,821
Other assets	16	17
Total assets	30,641	30,594
Deferred taxes	(51)
Debt	5,657	5,657
Other liabilities	200	114
Total liabilities	5,806	5,771
Common stock	21,982	21,843
Retained earnings	27,894	27,238
Accumulated other comprehensive income	769	880
Treasury stock, at cost	(25,810)	(25,138)
Total shareholders' equity	24,835	24,823
Total liabilities and shareholders' equity	30,641	30,594
Eliminations [Member]
Consolidating Balance Sheet
Investment in subsidiaries	(28,798)	(28,821)
Total assets	(28,798)	(28,821)
Common stock	(390)	(390)
Additional paid-in capital	(18,136)	(18,136)
Retained earnings	(8,838)	(8,733)
Accumulated other comprehensive income	(1,434)	(1,562)
Total shareholders' equity	(28,798)	(28,821)
Total liabilities and shareholders' equity	$ (28,798)	$ (28,821)