Note 3 - Fair Value Measurements - Financial Assets and Liabilities (Details) - USD ($) $ in Thousands		Oct. 31, 2017	Jan. 31, 2017
Liability related to the interest rate swap		$ (87)	$ (190)
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Money market mutual funds	[1]	114,859	116,043
Liability related to the interest rate swap	[2]
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Money market mutual funds	[1]
Liability related to the interest rate swap	[2]	$ (87)	$ (190)

[1] Money market mutual funds are recorded at fair value based upon quoted market prices.

[2] The liability related to the interest rate swap is recorded at fair value based upon a valuation model that uses relevant observable market inputs at quoted intervals, such as forward yield curves.