CONDENSED CONSOLIDATED BALANCE SHEETS (Parentheticals) - $ / shares	Dec. 31, 2015	Mar. 31, 2015
McKesson Corporation Stockholders’ Equity
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	100,000,000	100,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	800,000,000	800,000,000
Common stock, shares issued (in shares)	271,000,000	384,000,000
Treasury stock, shares (in shares)	42,000,000	152,000,000