Equity Investment (Detail) - TH2 - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jan. 31, 2020	Jan. 31, 2019	Jan. 31, 2020	Jan. 31, 2019	Jul. 31, 2019
Schedule of Equity Method Investments [Line Items]
Losses from investment	$ 2,652	$ 2,216	$ 4,747	$ 3,699
Loan to joint venture			4,527
Loan to joint venture, outstanding balance	$ 6,684		$ 6,684		$ 2,157

Amount of income (loss) for proportionate share of equity method investee's income (loss).

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