INVESTMENTS - Recognition and Measurement of OTTI (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
OTTI on Investments disclosures
Total OTTI losses recognized during the period	$ 0	$ 1
Less: portion of impairment loss recognized in AOCI (before taxes)	0	0
Net impairment losses recognized in earnings for securities that the Company does not intend to sell nor will likely be required to sell	0	1
Impairment losses recognized in earnings for securities that the Company intends to sell, would be more likely than not required to sell or will be subject to an issuer call deemed probable of exercise	12	464
Total impairment losses recognized in earnings	12	465
Securities available-for-sale (AFS)
OTTI on Investments disclosures
Total OTTI losses recognized during the period	0	1
Less: portion of impairment loss recognized in AOCI (before taxes)	0	0
Net impairment losses recognized in earnings for securities that the Company does not intend to sell nor will likely be required to sell	0	1
Impairment losses recognized in earnings for securities that the Company intends to sell, would be more likely than not required to sell or will be subject to an issuer call deemed probable of exercise	11	195
Total impairment losses recognized in earnings	11	196
Held-to-maturity securities
OTTI on Investments disclosures
Total OTTI losses recognized during the period	0	0
Less: portion of impairment loss recognized in AOCI (before taxes)	0	0
Net impairment losses recognized in earnings for securities that the Company does not intend to sell nor will likely be required to sell	0	0
Impairment losses recognized in earnings for securities that the Company intends to sell, would be more likely than not required to sell or will be subject to an issuer call deemed probable of exercise	1	7
Total impairment losses recognized in earnings	1	7
Other assets
OTTI on Investments disclosures
Total OTTI losses recognized during the period	0	0
Less: portion of impairment loss recognized in AOCI (before taxes)	0	0
Net impairment losses recognized in earnings for securities that the Company does not intend to sell nor will likely be required to sell	0	0
Impairment losses recognized in earnings for securities that the Company intends to sell, would be more likely than not required to sell or will be subject to an issuer call deemed probable of exercise	0	262
Total impairment losses recognized in earnings	$ 0	262
VENEZUELA | Securities available-for-sale (AFS)
OTTI on Investments disclosures
Total impairment losses recognized in earnings		$ 160