INVESTMENTS - Cumulative OTTI Credit Losses (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
AFS debt securities
Schedule of other-than-temporary impairment, credit losses recognized in earnings, roll forward
Balance at beginning of period	$ 726	$ 723	$ 733	$ 723
Credit impairments recognized in earnings on securities not previously impaired	0	2	0	2
Credit impairments recognized in earnings on securities that have been previously impaired	0	0	0	0
Reductions due to credit-impaired securities sold, transferred or matured	0	(1)	(7)	(1)
Balance at end of period	726	724	726	724
AFS debt securities | Mortgage-backed securities
Schedule of other-than-temporary impairment, credit losses recognized in earnings, roll forward
Balance at beginning of period	295	295	295	295
Credit impairments recognized in earnings on securities not previously impaired	0	0	0	0
Credit impairments recognized in earnings on securities that have been previously impaired	0	0	0	0
Reductions due to credit-impaired securities sold, transferred or matured	0	0	0	0
Balance at end of period	295	295	295	295
AFS debt securities | Foreign government securities
Schedule of other-than-temporary impairment, credit losses recognized in earnings, roll forward
Balance at beginning of period	170	171	171	171
Credit impairments recognized in earnings on securities not previously impaired	0	0	0	0
Credit impairments recognized in earnings on securities that have been previously impaired	0	0	0	0
Reductions due to credit-impaired securities sold, transferred or matured	0	0	(1)	0
Balance at end of period	170	171	170	171
AFS debt securities | Corporate
Schedule of other-than-temporary impairment, credit losses recognized in earnings, roll forward
Balance at beginning of period	112	113	118	113
Credit impairments recognized in earnings on securities not previously impaired	0	0	0	0
Credit impairments recognized in earnings on securities that have been previously impaired	0	0	0	0
Reductions due to credit-impaired securities sold, transferred or matured	0	(1)	(6)	(1)
Balance at end of period	112	112	112	112
AFS debt securities | Other debt securities
Schedule of other-than-temporary impairment, credit losses recognized in earnings, roll forward
Balance at beginning of period	149	144	149	144
Credit impairments recognized in earnings on securities not previously impaired	0	2	0	2
Credit impairments recognized in earnings on securities that have been previously impaired	0	0	0	0
Reductions due to credit-impaired securities sold, transferred or matured	0	0	0	0
Balance at end of period	149	146	149	146
HTM debt securities
Schedule of other-than-temporary impairment, credit losses recognized in earnings, roll forward
Balance at beginning of period	801	854	803	867
Credit impairments recognized in earnings on securities not previously impaired	0	0	0	0
Credit impairments recognized in earnings on securities that have been previously impaired	0	0	0	0
Reductions due to credit-impaired securities sold, transferred or matured	0	0	(2)	(13)
Balance at end of period	801	854	801	854
HTM debt securities | Mortgage-backed securities
Schedule of other-than-temporary impairment, credit losses recognized in earnings, roll forward
Balance at beginning of period	668	665	670	678
Credit impairments recognized in earnings on securities not previously impaired	0	0	0	0
Credit impairments recognized in earnings on securities that have been previously impaired	0	0	0	0
Reductions due to credit-impaired securities sold, transferred or matured	0	0	(2)	(13)
Balance at end of period	668	665	668	665
HTM debt securities | Corporate
Schedule of other-than-temporary impairment, credit losses recognized in earnings, roll forward
Balance at beginning of period	0	56	0	56
Credit impairments recognized in earnings on securities not previously impaired	0	0	0	0
Credit impairments recognized in earnings on securities that have been previously impaired	0	0	0	0
Reductions due to credit-impaired securities sold, transferred or matured	0	0	0	0
Balance at end of period	0	56	0	56
HTM debt securities | Other debt securities
Schedule of other-than-temporary impairment, credit losses recognized in earnings, roll forward
Balance at beginning of period	133	133	133	133
Credit impairments recognized in earnings on securities not previously impaired	0	0	0	0
Credit impairments recognized in earnings on securities that have been previously impaired	0	0	0	0
Reductions due to credit-impaired securities sold, transferred or matured	0	0	0	0
Balance at end of period	$ 133	$ 133	$ 133	$ 133