Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jul. 31, 2016	Jul. 31, 2015	Jul. 31, 2016	Jul. 31, 2015	Jan. 31, 2016
Income Tax Contingency [Line Items]
Income tax benefit (expense)	$ 741,000	$ 2,993,000	$ (472,000)	$ 2,232,000
Tax benefit on domestic deferred tax assets	0	0	0	0
Tax benefit on foreign deferred tax assets	$ 0	$ 0	$ 0	$ 0
Effective tax rate for continued operations	12.20%	11.30%	(3.50%)	6.90%
Unrecognized tax benefits	$ 10,200,000		$ 10,200,000		$ 10,800,000
Unrecognized tax benefits that would affect the effective tax rate if recognized	10,200,000		10,200,000		10,800,000
Possible decrease in unrecognized tax benefits due to settlements of audit issues	3,400,000		3,400,000
Liability for income tax-related interest and penalties	8,000,000		8,000,000		$ 7,800,000
Domestic Country [Member]
Income Tax Contingency [Line Items]
Deferred tax assets after valuation allowance	0		0
Foreign Tax Authority [Member]
Income Tax Contingency [Line Items]
Deferred tax assets after valuation allowance	800,000		800,000
Estimated taxable income to realize deferred tax asset	$ 2,600,000		$ 2,600,000