Fair Value (Assets and Liabilities at Fair Value) (Details) - USD ($)	Oct. 31, 2015	Jan. 31, 2015
Fair Value, Measurements, Recurring
Assets, Fair Value Disclosure [Abstract]
Money market funds	$ 79,212,000	$ 122,047,000
Derivative financial instruments	1,769,000	10,293,000
Total assets measured at fair value	80,981,000	132,340,000
Liabilities, Fair Value Disclosure [Abstract]
Derivative financial instruments	396,000	0
Total liabilities measured at fair value	396,000	0
Level 1 | Fair Value, Measurements, Recurring
Assets, Fair Value Disclosure [Abstract]
Money market funds	79,212,000	122,047,000
Derivative financial instruments	0	0
Total assets measured at fair value	79,212,000	122,047,000
Liabilities, Fair Value Disclosure [Abstract]
Derivative financial instruments	0	0
Total liabilities measured at fair value	0	0
Level 2 | Fair Value, Measurements, Recurring
Assets, Fair Value Disclosure [Abstract]
Money market funds	0	0
Derivative financial instruments	1,769,000	10,293,000
Total assets measured at fair value	1,769,000	10,293,000
Liabilities, Fair Value Disclosure [Abstract]
Derivative financial instruments	396,000	0
Total liabilities measured at fair value	396,000	0
Level 3 | Fair Value, Measurements, Recurring
Assets, Fair Value Disclosure [Abstract]
Money market funds	0	0
Derivative financial instruments	0	0
Total assets measured at fair value	0	0
Liabilities, Fair Value Disclosure [Abstract]
Derivative financial instruments	0	0
Total liabilities measured at fair value	0	0
Term Loan Facility
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gross borrowings outstanding, carrying amount	297,000,000	299,250,000
Gross borrowings outstanding, fair value	289,575,000	295,135,000
ABL Facility
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Credit facility, amount outstanding	$ 0	$ 0