INVESTMENTS - Cumulative OTTI Credit Losses (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
AFS debt securities
Schedule of other-than-temporary impairment, credit losses recognized in earnings, roll forward
Balance at beginning of period	$ 754	$ 733
Credit impairments recognized in earnings on securities not previously impaired	1	0
Credit impairments recognized in earnings on securities that have been previously impaired	0	0
Reductions due to credit-impaired securities sold, transferred or matured	(15)	(7)
Balance at end of period	740	726
AFS debt securities | Mortgage-backed securities
Schedule of other-than-temporary impairment, credit losses recognized in earnings, roll forward
Balance at beginning of period	294	295
Credit impairments recognized in earnings on securities not previously impaired	0	0
Credit impairments recognized in earnings on securities that have been previously impaired	0	0
Reductions due to credit-impaired securities sold, transferred or matured	0	0
Balance at end of period	294	295
AFS debt securities | State and municipal securities
Schedule of other-than-temporary impairment, credit losses recognized in earnings, roll forward
Balance at beginning of period	8	0
Credit impairments recognized in earnings on securities not previously impaired	0	0
Credit impairments recognized in earnings on securities that have been previously impaired	0	0
Reductions due to credit-impaired securities sold, transferred or matured	(8)	0
Balance at end of period	0	0
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
Credit impairments recognized in earnings on securities not previously impaired	0	0
Credit impairments recognized in earnings on securities that have been previously impaired	0	0
Reductions due to credit-impaired securities sold, transferred or matured	0	(1)
Balance at end of period	170	170
AFS debt securities | Corporate
Schedule of other-than-temporary impairment, credit losses recognized in earnings, roll forward
Balance at beginning of period	112	118
Credit impairments recognized in earnings on securities not previously impaired	1	0
Credit impairments recognized in earnings on securities that have been previously impaired	0	0
Reductions due to credit-impaired securities sold, transferred or matured	(3)	(6)
Balance at end of period	110	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	170	149
Credit impairments recognized in earnings on securities not previously impaired	0	0
Credit impairments recognized in earnings on securities that have been previously impaired	0	0
Reductions due to credit-impaired securities sold, transferred or matured	(4)	0
Balance at end of period	166	149
HTM debt securities
Schedule of other-than-temporary impairment, credit losses recognized in earnings, roll forward
Balance at beginning of period	800	803
Credit impairments recognized in earnings on securities not previously impaired	0	0
Credit impairments recognized in earnings on securities that have been previously impaired	0	0
Reductions due to credit-impaired securities sold, transferred or matured	0	(2)
Balance at end of period	800	801
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	670
Credit impairments recognized in earnings on securities not previously impaired	0	0
Credit impairments recognized in earnings on securities that have been previously impaired	0	0
Reductions due to credit-impaired securities sold, transferred or matured	0	(2)
Balance at end of period	668	668
HTM debt securities | Other debt securities
Schedule of other-than-temporary impairment, credit losses recognized in earnings, roll forward
Balance at beginning of period	132	133
Credit impairments recognized in earnings on securities not previously impaired	0	0
Credit impairments recognized in earnings on securities that have been previously impaired	0	0
Reductions due to credit-impaired securities sold, transferred or matured	0	0
Balance at end of period	$ 132	$ 133