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BASIS OF PRESENTATION AND ACCOUNTING CHANGES - Accounting Changes (Details) - USD ($) $ in Millions	Mar. 31, 2017	Dec. 31, 2016	Jan. 01, 2016
New Accounting Pronouncements or Change in Accounting Principle
AOCI	$ (30,917)	$ (32,381)
Retained earnings	149,731	$ 146,477
Accounting Standards Update 2016-01 \| New Accounting Pronouncement, Early Adoption, Effect
New Accounting Pronouncements or Change in Accounting Principle
AOCI			$ (15)
Retained earnings			$ 15
Pro Forma \| Accounting Standards Update 2016-16
New Accounting Pronouncements or Change in Accounting Principle
Increase in DTAs	500
Decrease in prepaid taxes	$ 500