Investments (Fixed Maturity and Equity Securities Available-For-Sale by Sector) (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013	Dec. 31, 2012
Available-for-sale Securities [Abstract]
Amortized Cost	$ 341,198	$ 333,599
Cost or Amortized Cost	3,111	3,012
Gross Unrealized OTTI Loss	105	218	361
Fixed maturity securities available-for-sale, at estimated fair value (amortized cost: $341,198 and $333,599, respectively; includes $4,097 and $4,005, respectively, relating to variable interest entities)	368,070	350,187
Equity securities	3,689	3,402
Fixed maturity securities [Member]
Available-for-sale Securities [Abstract]
Amortized Cost	341,198	333,599
Gross Unrealized Gain	28,596	21,180
Gross Unrealized Temporary Loss	1,619	4,374
Gross Unrealized OTTI Loss	105	218
Fixed maturity securities available-for-sale, at estimated fair value (amortized cost: $341,198 and $333,599, respectively; includes $4,097 and $4,005, respectively, relating to variable interest entities)	368,070	350,187
U.S. corporate securities [Member]
Available-for-sale Securities [Abstract]
Amortized Cost	99,000	100,203
Gross Unrealized Gain	9,522	7,495
Gross Unrealized Temporary Loss	548	1,229
Gross Unrealized OTTI Loss	0	0
Fixed maturity securities available-for-sale, at estimated fair value (amortized cost: $341,198 and $333,599, respectively; includes $4,097 and $4,005, respectively, relating to variable interest entities)	107,974	106,469
Foreign corporate securities [Member]
Available-for-sale Securities [Abstract]
Amortized Cost	57,799	59,778
Gross Unrealized Gain	4,477	3,939
Gross Unrealized Temporary Loss	392	565
Gross Unrealized OTTI Loss	7	0
Fixed maturity securities available-for-sale, at estimated fair value (amortized cost: $341,198 and $333,599, respectively; includes $4,097 and $4,005, respectively, relating to variable interest entities)	61,877	63,152
Foreign government debt securities [Member]
Available-for-sale Securities [Abstract]
Amortized Cost	51,267	50,717
Gross Unrealized Gain	5,319	4,107
Gross Unrealized Temporary Loss	190	387
Gross Unrealized OTTI Loss	0	0
Fixed maturity securities available-for-sale, at estimated fair value (amortized cost: $341,198 and $333,599, respectively; includes $4,097 and $4,005, respectively, relating to variable interest entities)	56,396	54,437
RMBS [Member]
Available-for-sale Securities [Abstract]
Amortized Cost	39,011	34,167
Gross Unrealized Gain	1,950	1,584
Gross Unrealized Temporary Loss	244	490
Gross Unrealized OTTI Loss	98	206
Fixed maturity securities available-for-sale, at estimated fair value (amortized cost: $341,198 and $333,599, respectively; includes $4,097 and $4,005, respectively, relating to variable interest entities)	40,619	35,055
U.S. Treasury and agency securities [Member]
Available-for-sale Securities [Abstract]
Amortized Cost	52,275	43,928
Gross Unrealized Gain	4,660	2,251
Gross Unrealized Temporary Loss	73	1,056
Gross Unrealized OTTI Loss	0	0
Fixed maturity securities available-for-sale, at estimated fair value (amortized cost: $341,198 and $333,599, respectively; includes $4,097 and $4,005, respectively, relating to variable interest entities)	56,862	45,123
CMBS [Member]
Available-for-sale Securities [Abstract]
Amortized Cost	14,224	16,115
Gross Unrealized Gain	482	605
Gross Unrealized Temporary Loss	57	170
Gross Unrealized OTTI Loss	0	0
Fixed maturity securities available-for-sale, at estimated fair value (amortized cost: $341,198 and $333,599, respectively; includes $4,097 and $4,005, respectively, relating to variable interest entities)	14,649	16,550
ABS [Member]
Available-for-sale Securities [Abstract]
Amortized Cost	14,656	15,458
Gross Unrealized Gain	265	296
Gross Unrealized Temporary Loss	68	171
Gross Unrealized OTTI Loss	0	12
Fixed maturity securities available-for-sale, at estimated fair value (amortized cost: $341,198 and $333,599, respectively; includes $4,097 and $4,005, respectively, relating to variable interest entities)	14,853	15,571
State and political subdivision securities [Member]
Available-for-sale Securities [Abstract]
Amortized Cost	12,966	13,233
Gross Unrealized Gain	1,921	903
Gross Unrealized Temporary Loss	47	306
Gross Unrealized OTTI Loss	0	0
Fixed maturity securities available-for-sale, at estimated fair value (amortized cost: $341,198 and $333,599, respectively; includes $4,097 and $4,005, respectively, relating to variable interest entities)	14,840	13,830
Equity Securities [Member]
Available-for-sale Securities [Abstract]
Cost or Amortized Cost	3,111	3,012
Gross Unrealized Gain	618	507
Gross Unrealized Temporary Loss	40	117
Gross Unrealized OTTI Loss	0	0
Equity securities	3,689	3,402
Common Stock [Member]
Available-for-sale Securities [Abstract]
Cost or Amortized Cost	2,027	1,927
Gross Unrealized Gain	550	431
Gross Unrealized Temporary Loss	3	5
Gross Unrealized OTTI Loss	0	0
Equity securities	2,574	2,353
Non-redeemable preferred stock [Member]
Available-for-sale Securities [Abstract]
Cost or Amortized Cost	1,084	1,085
Gross Unrealized Gain	68	76
Gross Unrealized Temporary Loss	37	112
Gross Unrealized OTTI Loss	0	0
Equity securities	$ 1,115	$ 1,049