Commitments and Contingencies - Future Minimum Lease Payments under Non-cancellable Capital and Operating Leases (Details) $ in Thousands	Jul. 31, 2018 USD ($)
Capital Leases
Capital Leases, Remainder of 2019	$ 12,135
Capital Leases, 2020	19,343
Capital Leases, 2021	15,290
Capital Leases, 2022	7,436
Capital Leases, 2023	961
Capital Leases, Total minimum lease payments	55,165
Capital Leases, Less: amount representing interest	(2,047)
Capital Leases, Present value of minimum lease payments	53,118
Operating Leases
Operating Leases, net of Sublease Income, Remainder of 2019	17,442
Operating Leases, net of Sublease Income, 2020	35,855
Operating Leases, net of Sublease Income, 2021	36,576
Operating Leases, net of Sublease Income, 2022	34,350
Operating Leases, net of Sublease Income, 2023	26,453
Operating Leases, net of Sublease Income, Thereafter	143,298
Operating Leases, net of Sublease Income, Total minimum lease payments	$ 293,974

Amount of minimum lease payments for capital leases.

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-SubTopic 30
-Section 50
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Amount of minimum lease payments for capital leases 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 minimum lease payments for capital leases due in the fourth 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 minimum lease payments for capital leases 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 minimum lease payments for capital leases 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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Amount necessary to reduce net minimum lease payments to present value for capital leases.

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Present value of minimum lease payments for capital leases net of executory costs, including amounts paid by the lessee to the lessor for insurance, maintenance and taxes.

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Amount of minimum lease payments for capital leases due in the remainder of the 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 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 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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