Organization and Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)	12 Months Ended
	Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2016
Partnership Organization And Basis Of Presentation [Line Items]
Services pursuant to contracts term	12 months
Support services term	12 months
Additional charges	$ 0
Salvage value assigned to property and equipment	$ 0
Customers warranty against defects	3 months
Customer relationships
Partnership Organization And Basis Of Presentation [Line Items]
Intangible assets amortization period	8 years
Building
Partnership Organization And Basis Of Presentation [Line Items]
Estimated useful lives	30 years
Property Improvements
Partnership Organization And Basis Of Presentation [Line Items]
Estimated useful lives	10 years
Maximum
Partnership Organization And Basis Of Presentation [Line Items]
Lease period	1 year	1 year	1 year
Contracts receivable term	2 years
Liquid investments maturity period	3 months
Short-term investments maturity period	12 months
Estimated useful lives	7 years
Maximum | Proprietary Rights Developed Technology and Amortizable Trade Names
Partnership Organization And Basis Of Presentation [Line Items]
Intangible assets amortization period	15 years
Maximum | Patents
Partnership Organization And Basis Of Presentation [Line Items]
Intangible assets amortization period	9 years
Maximum | Recording channels
Partnership Organization And Basis Of Presentation [Line Items]
Estimated useful lives	7 years
Maximum | Other peripheral equipment
Partnership Organization And Basis Of Presentation [Line Items]
Estimated useful lives	10 years
Minimum
Partnership Organization And Basis Of Presentation [Line Items]
Short-term investments maturity period	3 months
Estimated useful lives	3 years
Minimum | Proprietary Rights Developed Technology and Amortizable Trade Names
Partnership Organization And Basis Of Presentation [Line Items]
Intangible assets amortization period	10 years
Minimum | Patents
Partnership Organization And Basis Of Presentation [Line Items]
Intangible assets amortization period	8 years
Minimum | Recording channels
Partnership Organization And Basis Of Presentation [Line Items]
Estimated useful lives	5 years
Minimum | Other peripheral equipment
Partnership Organization And Basis Of Presentation [Line Items]
Estimated useful lives	2 years