EMPLOYEE STOCK BENEFIT PLANS Share-based Payment Arrangement, Nonvested Award, Cost (Details) $ in Millions	3 Months Ended
	Jun. 30, 2020 USD ($)
Share-based Payment Arrangement, Option [Member]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 70
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition	1 year 8 months 12 days
Restricted Stock Units (RSUs) [Member]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 1,182
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition	2 years 8 months 12 days
Market share units [Member]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 65
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition	3 years 1 month 6 days
Performance Shares [Member]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 111
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition	2 years