Note 10 - Stockholders' Equity - Dividends (Details) - USD ($) $ / shares in Units, $ in Thousands			6 Months Ended
Jun. 11, 2020	Apr. 07, 2020	Jul. 31, 2020	Jul. 31, 2019
Record Date	Jun. 25, 2020	Apr. 22, 2020
Payable	Jul. 07, 2020	Apr. 29, 2020
Amount	$ 1,448	$ 1,431	$ 2,879	$ 2,761
Common Class A [Member]
Dividend (in dollars per share)	$ 0.072	$ 0.072
Common Class B [Member]
Dividend (in dollars per share)	$ 0.06	$ 0.06

Date the declared dividend will be paid, in CCYY-MM-DD format.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=121583591&loc=d3e4304-108586

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

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The per share amount of a dividend declared, but not paid, as of the financial reporting date.

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Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

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