Leases - Summary of Maturities of Operating and Finance Lease Liabilities (Parenthetical) (Details) $ in Millions	Oct. 31, 2020 USD ($)
Leases [Abstract]
Non-cancellable sublease proceeds for the year ending January 31, 2021	$ 1.9
Non-cancellable sublease proceeds for the year ending January 31, 2022	9.9
Non-cancellable sublease proceeds for the year ending January 31, 2023	8.3
Non-cancellable sublease proceeds for the year ending January 31, 2024	2.2
Non-cancellable sublease proceeds for the year ending January 31, 2025	$ 2.2

Operating leases future minimum payments sublease rentals proceeds due in next twelve months.

No definition available.

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Operating leases future minimum payments sublease rentals proceeds due in year four.

No definition available.

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Operating leases future minimum payments sublease rentals proceeds due in year three.

No definition available.

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Operating leases future minimum payments sublease rentals proceeds due in year two.

No definition available.

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Operating leases future minimum payments sublease rentals proceeds due remainder of fiscal year.

No definition available.

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No definition available.