Leases (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Apr. 30, 2020	Apr. 30, 2020	Jul. 31, 2019
Lease, Cost
Operating lease cost	$ 517	$ 1,551
Short-term operating lease cost	190	590
Operating cash flows from operating leases	$ 430	$ 1,285
Weighted-average remaining lease term - operating leaes	10 years 7 months 6 days	10 years 7 months 6 days
Weighted-average discount rate - operating leases	4.02%	4.02%
Lessee, Operating Lease, Liability, Payment, Due, Rolling Maturity
2020	$ 1,912	$ 1,912
2021	1,507	1,507
2022	983	983
2023	781	781
2024	767	767
Thereafter	6,320	6,320
Total	12,270	12,270
Less: imputed interest	(2,424)	(2,424)
Net lease obligation	$ 9,846	$ 9,846
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity
2020			$ 2,255
2021			1,640
2022			1,513
2023			1,038
2024			899
Thereafter			$ 7,422

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Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

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Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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