Note 11 - Stockholders' Equity - Dividends (Details) - USD ($)				9 Months Ended
Sep. 04, 2019	Jun. 24, 2019	Apr. 09, 2019	Oct. 31, 2019	Oct. 31, 2018
Record Date	Sep. 18, 2019	Jul. 10, 2019	Apr. 23, 2019
Payable	Sep. 25, 2019	Jul. 17, 2019	May 03, 2019
Amount	$ 1,426	$ 1,387,000	$ 1,374,000	$ 4,187,000	$ 4,105,000
Common Class A [Member]
Dividend Per Share (in dollars per share)	$ 0.072	$ 0.072	$ 0.072
Common Class B [Member]
Dividend Per Share (in dollars per share)	$ 0.06	$ 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=98513485&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=27012166&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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