Property and Equipment (Details) - USD ($) $ in Thousands	3 Months Ended
Apr. 30, 2020	Apr. 30, 2019	Jan. 31, 2020
Property, Plant and Equipment
Property and equipment, gross	$ 292,764		$ 280,425
Less: accumulated depreciation and amortization	(124,543)		(123,497)
Property and equipment, net	168,221		156,928
Depreciation and amortization expense on Property and Equipment, net	5,800	$ 6,300
Computer equipment and software
Property, Plant and Equipment
Property and equipment, gross	100,361		109,892
Furniture and fixtures
Property, Plant and Equipment
Property and equipment, gross	31,391		28,568
Leasehold and building improvements
Property, Plant and Equipment
Property and equipment, gross	161,012		141,965
Leasehold improvements not in service
Property, Plant and Equipment
Property and equipment, gross	$ 66,500		$ 46,500

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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