Fair Value Measurements (Details 4) - USD ($) $ in Millions		Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014	Dec. 31, 2013
Financial assets:
Cash and cash equivalents		$ 894	$ 1,343	$ 1,310	$ 1,639
Mortgage loans		994	1,117
Policy loans		221	228
Financial liabilities:
Long-term debt		880	1,061
Level 1 [Member]
Financial assets:
Cash and cash equivalents		894	1,343
Mortgage loans		0	0
Policy loans		0	0
Total financial assets not accounted for at fair value		894	1,343
Financial liabilities:
Annuity benefits accumulated	[1]	0	0
Long-term debt		0	0
Total financial liabilities not accounted for at fair value		0	0
Level 2 [Member]
Financial assets:
Cash and cash equivalents		0	0
Mortgage loans		0	0
Policy loans		0	0
Total financial assets not accounted for at fair value		0	0
Financial liabilities:
Annuity benefits accumulated	[1]	0	0
Long-term debt		962	1,106
Total financial liabilities not accounted for at fair value		962	1,106
Level 3 [Member]
Financial assets:
Cash and cash equivalents		0	0
Mortgage loans		1,005	1,124
Policy loans		221	228
Total financial assets not accounted for at fair value		1,226	1,352
Financial liabilities:
Annuity benefits accumulated	[1]	25,083	23,187
Long-term debt		25	74
Total financial liabilities not accounted for at fair value		25,108	23,261
Carrying Value [Member]
Financial assets:
Cash and cash equivalents		894	1,343
Mortgage loans		994	1,117
Policy loans		221	228
Total financial assets not accounted for at fair value		2,109	2,688
Financial liabilities:
Annuity benefits accumulated	[1]	25,825	23,561
Long-term debt		887	1,061
Total financial liabilities not accounted for at fair value		26,712	24,622
Fair Value [Member]
Financial assets:
Cash and cash equivalents		894	1,343
Mortgage loans		1,005	1,124
Policy loans		221	228
Total financial assets not accounted for at fair value		2,120	2,695
Financial liabilities:
Annuity benefits accumulated	[1]	25,083	23,187
Long-term debt		987	1,180
Total financial liabilities not accounted for at fair value		$ 26,070	$ 24,367

[1] Excludes $201 million and $203 million of life contingent annuities in the payout phase at September 30, 2015 and December 31, 2014, respectively.