Note 12 - Subsequent Event (Details Textual) - $ / shares		3 Months Ended
Nov. 01, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020
Common Stock, Dividends, Per Share, Declared (in dollars per share)		$ 0.20	$ 0.20	$ 0.20	$ 0.20	$ 0.20	$ 0.20
Subsequent Event [Member]
Common Stock, Dividends, Per Share, Declared (in dollars per share)	$ 0.20

Aggregate dividends declared during the period for each share of common stock outstanding.

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

Name:	us-gaap_CommonStockDividendsPerShareDeclared
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	duration