Consolidated Statements of Stockholders' Equity (Parenthetical) - $ / shares	3 Months Ended		6 Months Ended
	Jan. 31, 2020	Jan. 31, 2019	Jan. 31, 2020	Jan. 31, 2019
Equity [Abstract]
Cash dividends, per common share (in dollars per share)	$ 0.40	$ 0.39	$ 0.80	$ 0.78