Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Jul. 31, 2018	Jul. 31, 2017
Statement of Financial Position [Abstract]
Accounts receivable, allowance for doubtful accounts	$ 1,149	$ 1,808
Preferred Stock, par value (in dollars per share)	$ 1.00	$ 1.00
Preferred Stock, authorized shares	1,000,000	1,000,000
Preferred Stock, shares issued	0	0
Common Stock, par value (in dollars per share)	$ 0.10	$ 0.10
Common Stock, authorized shares	75,000,000	75,000,000
Common Stock, shares issued	46,243,582	46,194,374
Common Stock, shares outstanding	41,706,084	41,728,934
Treasury Stock, shares	4,537,498	4,465,440