STOCKHOLDERS' EQUITY - Summary of Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Jun. 30, 2020	Jan. 01, 2020	Dec. 31, 2019	Jun. 30, 2019	Jan. 01, 2019	Dec. 31, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax					$ (859)			$ (1,416)
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	$ 38,118	$ 41,912	$ 38,118	$ 41,912	38,118	$ 37,577		41,556	$ 42,576		$ 95,900
Other comprehensive income (loss) before reclassifications			539	(739)
Amounts reclassified from accumulated other comprehensive income			18	106
Net other comprehensive income (loss)			557	(633)
Total other comprehensive income (loss)	610	(699)	556	(621)
Spin-off of Dow and Corteva				(50,487)
Ending balance	38,118	41,912	38,118	41,912
Tax expense from income taxes related to other comprehensive income items	1	(6)	3	(44)
Spin-off of Dow and Corteva				11,498
Unrealized Gains (Losses) on Investments
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	0	0	0	0	0		$ 0			$ (51)
Other comprehensive income (loss) before reclassifications			0	68
Amounts reclassified from accumulated other comprehensive income			0	(1)
Net other comprehensive income (loss)			0	67
Ending balance	0	0	0	0
Tax expense from income taxes related to other comprehensive income items	0	0	0	(18)
Spin-off of Dow and Corteva				(16)
Cumulative translation adjustments
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(522)	(1,435)	(522)	(1,435)	(522)		(1,070)			(3,785)
Other comprehensive income (loss) before reclassifications			548	(811)
Amounts reclassified from accumulated other comprehensive income			0	(18)
Net other comprehensive income (loss)			548	(829)
Ending balance	(522)	(1,435)	(522)	(1,435)
Tax expense from income taxes related to other comprehensive income items	0	0	0	(1)
Spin-off of Dow and Corteva				3,179
Pension and other post-employment benefit plans
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(336)	(93)	(336)	(93)	(336)		(345)			(8,476)
Other comprehensive income (loss) before reclassifications			(9)	47
Amounts reclassified from accumulated other comprehensive income			18	140
Net other comprehensive income (loss)			9	187
Ending balance	(336)	(93)	(336)	(93)
Tax expense from income taxes related to other comprehensive income items	1	(6)	3	(41)
Spin-off of Dow and Corteva				8,196
Derivative Instruments
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(1)	(1)	(1)	(1)	(1)		(1)			(82)
Other comprehensive income (loss) before reclassifications			0	(43)
Amounts reclassified from accumulated other comprehensive income			0	(15)
Net other comprehensive income (loss)			0	(58)
Ending balance	(1)	(1)	(1)	(1)
Tax expense from income taxes related to other comprehensive income items	0	0	0	16
Spin-off of Dow and Corteva				139
Total
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(859)	(1,529)	(859)	(1,529)	$ (859)	$ (1,465)	$ (1,416)	$ (1,416)	$ (831)	$ (12,394)	$ (12,394)
Total other comprehensive income (loss)	606	(698)	557	(633)
Spin-off of Dow and Corteva				11,498
Ending balance	$ (859)	$ (1,529)	$ (859)	$ (1,529)