Consolidating Financial Statements (details) - Consolidating Balance Sheet (Unaudited) - USD ($) shares in Millions, $ in Millions	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015	Dec. 31, 2014
Consolidating Balance Sheet
Fixed maturities, available for sale, at fair value	$ 61,985	$ 60,658
Equity securities, available for sale, at fair value	710	705
Real estate investments	927	989
Short-term securities	4,587	4,671
Other investments	3,469	3,447
Total investments	71,678	70,470
Cash	361	380	$ 308	$ 374
Investment income accrued	599	642
Premiums receivable	6,845	6,437
Reinsurance recoverables	8,803	8,910
Ceded unearned premiums	805	656
Deferred acquisition costs	1,899	1,849
Deferred taxes		296
Contractholder receivables	4,419	4,374
Goodwill	3,588	3,573
Other intangible assets	275	279
Other assets	2,408	2,318
Total assets	101,680	100,184
Claims and claim adjustment expense reserves	48,640	48,295
Unearned premium reserves	12,331	11,971
Contractholder payables	4,419	4,374
Payables for reinsurance premiums	438	296
Deferred taxes	82
Debt	6,344	6,344
Other liabilities	5,260	5,306
Total liabilities	77,514	76,586
Common stock	22,269	22,172
Retained earnings	30,454	29,945
Accumulated other comprehensive income (loss)	414	(157)
Treasury stock, at cost	(28,971)	(28,362)
Total shareholders' equity	24,166	23,598	24,847
Total liabilities and shareholders' equity	101,680	100,184
Fixed maturities, available for sale, amortized cost	59,490	58,878
Equity securities, available for sale, cost	$ 528	$ 528
Common stock, shares authorized	1,750.0	1,750.0
Common stock, shares issued	292.4	295.9
Common stock, shares outstanding	292.4	295.9
Treasury stock, at cost, shares	473.2	467.6
TPC [Member]
Consolidating Balance Sheet
Fixed maturities, available for sale, at fair value	$ 42,898	$ 42,289
Equity securities, available for sale, at fair value	193	189
Real estate investments	55	56
Short-term securities	2,100	1,947
Other investments	2,563	2,516
Total investments	47,809	46,997
Cash	211	225	195	221
Investment income accrued	420	453
Premiums receivable	4,599	4,336
Reinsurance recoverables	5,937	5,849
Ceded unearned premiums	737	610
Deferred acquisition costs	1,702	1,660
Deferred taxes		178
Contractholder receivables	3,432	3,387
Goodwill	2,584	2,573
Other intangible assets	202	203
Other assets	2,070	1,958
Total assets	69,703	68,429
Claims and claim adjustment expense reserves	32,378	31,965
Unearned premium reserves	8,603	8,335
Contractholder payables	3,432	3,387
Payables for reinsurance premiums	267	175
Deferred taxes	108
Debt	692	693
Other liabilities	3,949	3,958
Total liabilities	49,429	48,513
Additional paid-in capital	11,634	11,634
Retained earnings	7,848	7,888
Accumulated other comprehensive income (loss)	792	394
Total shareholders' equity	20,274	19,916
Total liabilities and shareholders' equity	69,703	68,429
Other Subsidiaries [Member]
Consolidating Balance Sheet
Fixed maturities, available for sale, at fair value	19,039	18,323
Equity securities, available for sale, at fair value	374	375
Real estate investments	872	933
Short-term securities	861	1,178
Other investments	905	930
Total investments	22,051	21,739
Cash	148	153	111	151
Investment income accrued	176	185
Premiums receivable	2,246	2,101
Reinsurance recoverables	2,866	3,061
Ceded unearned premiums	68	46
Deferred acquisition costs	197	189
Deferred taxes		83
Contractholder receivables	987	987
Goodwill	1,004	1,000
Other intangible assets	73	76
Other assets	322	344
Total assets	30,138	29,964
Claims and claim adjustment expense reserves	16,262	16,330
Unearned premium reserves	3,728	3,636
Contractholder payables	987	987
Payables for reinsurance premiums	171	121
Deferred taxes	4
Other liabilities	1,169	1,221
Total liabilities	22,321	22,295
Common stock	390	390
Additional paid-in capital	6,499	6,499
Retained earnings	673	688
Accumulated other comprehensive income (loss)	255	92
Total shareholders' equity	7,817	7,669
Total liabilities and shareholders' equity	30,138	29,964
Travelers [Member]
Consolidating Balance Sheet
Fixed maturities, available for sale, at fair value	48	46
Equity securities, available for sale, at fair value	143	141
Short-term securities	1,626	1,546
Other investments	1	1
Total investments	1,818	1,734
Cash	2	2	$ 2	$ 2
Investment income accrued	3	4
Deferred taxes		35
Investment in subsidiaries	28,081	27,573
Other assets	16	16
Total assets	29,920	29,364
Deferred taxes	(30)
Debt	5,652	5,651
Other liabilities	142	127
Total liabilities	5,764	5,778
Common stock	22,269	22,172
Retained earnings	30,444	29,933
Accumulated other comprehensive income (loss)	414	(157)
Treasury stock, at cost	(28,971)	(28,362)
Total shareholders' equity	24,156	23,586
Total liabilities and shareholders' equity	29,920	29,364
Eliminations [Member]
Consolidating Balance Sheet
Investment in subsidiaries	(28,081)	(27,573)
Total assets	(28,081)	(27,573)
Common stock	(390)	(390)
Additional paid-in capital	(18,133)	(18,133)
Retained earnings	(8,511)	(8,564)
Accumulated other comprehensive income (loss)	(1,047)	(486)
Total shareholders' equity	(28,081)	(27,573)
Total liabilities and shareholders' equity	$ (28,081)	$ (27,573)