Income Taxes - Reconciliation of Expected to Actual Income Tax Expense (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Jan. 31, 2017	Oct. 31, 2016	Jul. 31, 2016	Apr. 30, 2016	Jan. 31, 2016	Oct. 31, 2015	Jul. 31, 2015	Apr. 30, 2015	Jan. 31, 2017	Jan. 31, 2016	Jan. 31, 2015
Reconciliation of expected to actual income tax expense
Federal income tax (benefit) expense at 34%									$ (10,655)	$ (9,436)	$ (3,463)
Changes in tax rates										(82)
Permanent differences									38	509	(224)
Foreign effective tax rate differential									1,979	1,609	540
Potential tax, penalties and interest resulting from uncertain tax positions										(236)	(172)
Foreign withholding taxes									671	717	920
Election to deduct foreign taxes in prior years U.S. income tax returns										2,610
Valuation allowance on deferred tax assets									10,056	15,477	1,379
Other									(275)	(191)	26
Income tax expense (benefit)	$ 1,308	$ (228)	$ 435	$ 299	$ 14,675	$ (746)	$ (2,797)	$ (155)	$ 1,814	$ 10,977	$ (994)