Note 2 - Summary of Significant Accounting Policies - Fair Value Measurements (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Summary of Significant Accounting Policies.
Excess fair value of debt over carrying value	$ 36.0	$ 38.0
Other income recognized related to Coronavirus Aid, Relief and Economic Security Act Employee Retention Tax Credit	$ 5.4

Amount of revenue and income classified as other.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.4)
-URI https://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263

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Balance Type:	credit
Period Type:	duration