OTHER STOCK-RELATED INFORMATION - Schedule of Cash Proceeds and Tax Benefit from Awards (Details) - USD ($) shares in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Income tax benefit recognized in earnings	$ 138	$ 274	$ 148
Excess of actual tax deductions over amounts assumed recognized in equity	$ 0	$ 0	$ 167
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options exercised (in shares)	30,774	56,973	65,764
Cash received from stock options exercised	$ 528	$ 1,037	$ 1,098