Property and Equipment, Net - Summary of Property and Equipment (Detail) - USD ($) $ in Thousands	Apr. 30, 2018	Jan. 31, 2018
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 945,556	$ 855,587
Less accumulated depreciation and amortization	(334,263)	(308,978)
Property and equipment, net	611,293	546,609
Land
Property, Plant and Equipment [Line Items]
Property and equipment, gross	9,641	8,451
Buildings
Property, Plant and Equipment [Line Items]
Property and equipment, gross	302,542	255,093
Computers, equipment, and software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	440,660	411,177
Computers, equipment, and software acquired under capital leases
Property, Plant and Equipment [Line Items]
Property and equipment, gross	13,414	13,848
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	36,956	34,809
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	142,343	132,209
Construction in Progress Related to Owned Real Estate Projects
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 199,000	$ 177,000

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(13))
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