CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY (Parentheticals) - USD ($) $ in Millions	1 Months Ended	3 Months Ended	12 Months Ended
	Jul. 31, 2020	Jun. 30, 2020	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2019
Statement of Stockholders' Equity [Abstract]
Cash dividends declared per common share (in dollars per share)	$ 0.42	$ 0.41	$ 1.67	$ 1.62	$ 1.51
Stock Repurchased During Period, Value			$ (750)	$ (1,934)	$ (1,627)