Note 4 - Fair Value Measurements - Financial Assets and Liabilities (Details) - Fair Value, Recurring [Member] - USD ($) $ in Thousands	Oct. 31, 2020	Jan. 31, 2020
Fair Value, Inputs, Level 1 [Member] \| Money Market Funds [Member]
Cash and cash equivalents	$ 116,963	$ 107,319
Fair Value, Inputs, Level 1 [Member] \| Certificates of Deposit [Member]
Cash and cash equivalents	8,060	14,917
Fair Value, Inputs, Level 2 [Member]
Liability related to the interest rate swap	$ (381)	$ (232)

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13433-108611

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313

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