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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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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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Supplemental financial statement information (Property and equipment) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2019	Jul. 31, 2018	Jul. 31, 2019	Jul. 31, 2018	Jan. 31, 2019
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 20,768		$ 20,768		$ 17,301
Accumulated depreciation	(10,895)		(10,895)		(9,078)
Property and equipment, net	9,873		9,873		8,223
Depreciation expense	1,000	$ 800	1,800	$ 1,700
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	4,288		4,288		3,583
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	5,201		5,201		4,476
Computer equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 11,279		$ 11,279		$ 9,242