Commitments and Contingencies - Annual Required Payments (Details) $ in Thousands	12 Months Ended
Jul. 31, 2017 USD ($)
Minimum commitments under noncancelable operating leases
2018	$ 6,522
2019	5,278
2020	3,779
2021	2,719
2022	1,231
Thereafter	2,454
Total	21,983
Jet Prep Ltd.
Total contractual obligations
Assumed contingent obligation	1,138
Decrease in contingent liability	$ 283

Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

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The amount of liability arising from an inherited contingency (as defined) which has been recognized as of the acquisition date.

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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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 fifth 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 third 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 after the fifth 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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