Stockholders' Equity (Details) - 2018 Authorization [Member] - USD ($)		3 Months Ended
	May 31, 2018	May 31, 2018	Jan. 31, 2018
Class A and Class B [Member]
Equity, Class of Treasury Stock [Line Items]
Repurchase Authorization			$ 3,000,000,000.0
Class A Common Stock [Member]
Equity, Class of Treasury Stock [Line Items]
Dollar Value of Shares Repurchased	$ 591,600,000	$ 100,000,000
Number of Shares Repurchased	2,730,375	450,508