Intangible Assets - Details of Intangible Assets (Detail) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jul. 31, 2019	Jan. 31, 2019
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 54,470	$ 54,470
Accumulated amortization	(33,032)	(29,949)
Intangible assets, net	21,438	24,521
Existing technology
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	3,880	3,880
Accumulated amortization	(3,853)	(3,834)
Intangible assets, net	$ 27	$ 46
Remaining useful life (in years)	8 months 12 days	1 year 2 months 12 days
Database
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 4,939	$ 4,939
Accumulated amortization	(4,699)	(4,521)
Intangible assets, net	$ 240	$ 418
Remaining useful life (in years)	8 months 12 days	1 year 2 months 12 days
Customer contracts and relationships
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 33,643	$ 33,643
Accumulated amortization	(14,027)	(12,350)
Intangible assets, net	$ 19,616	$ 21,293
Remaining useful life (in years)	6 years 2 months 12 days	6 years 7 months 6 days
Software
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 10,867	$ 10,867
Accumulated amortization	(9,312)	(8,156)
Intangible assets, net	$ 1,555	$ 2,711
Remaining useful life (in years)	8 months 12 days	1 year 2 months 12 days
Brand
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 1,141	$ 1,141
Accumulated amortization	$ (1,141)	(1,088)
Intangible assets, net		$ 53
Remaining useful life (in years)	0 days	2 months 12 days