EARNINGS PER COMMON SHARE - ADDITIONAL INFORMATION (Details) - USD ($) $ / shares in Thousands, shares in Millions, $ in Millions	3 Months Ended					9 Months Ended
	Sep. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020	Jul. 28, 2021
Earnings Per Share [Line Items]
Antidilutive common stock options not included in the computation of diluted earnings per common share (in shares)	0.9		3.5
Earnings per share, potentially dilutive securities excluded from computation of earnings per share (in shares)							0.9
Treasury stock, shares, acquired (in shares)						1.5
Treasury shares purchased		$ 90		$ 0	$ 140	$ 90
Treasury stock acquired, average cost per share (in usd per share)						$ 60,620
Stock repurchase program, authorized amount								$ 1,000
Stock Options And Restricted Stock Units
Earnings Per Share [Line Items]
Antidilutive common stock options not included in the computation of diluted earnings per common share (in shares)						0.9
Common Stock
Earnings Per Share [Line Items]
Antidilutive common stock options not included in the computation of diluted earnings per common share (in shares)							3.2