Schedule II - Valuation and Qualifying Accounts (Detail) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2017	Jan. 31, 2016	Jan. 31, 2015
Allowance for Doubtful Accounts [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	$ 5,821	$ 6,339	$ 3,833
Charged to Costs and Expenses	737	2,069	2,834
Charged to Other Accounts	(31)	404	(332)
Deductions Describe	(623)	(2,991)	4
Balance at End of Period	5,904	5,821	6,339
Allowance for Obsolete Equipment and Inventory [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	900	750	1,032
Charged to Costs and Expenses	116	208	(60)
Charged to Other Accounts	(41)	(58)	(151)
Deductions Describe	(23)		(71)
Balance at End of Period	$ 952	$ 900	$ 750