Note 16 - Benefit Plans - Weighted-average Assumptions Used to Determine Net Periodic Pension (Benefit) Cost (Details)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Discount Rate	4.24%	3.60%	4.14%
Expected long-term rate of return on plan assets	6.60%	6.19%	6.58%

Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(3)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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Balance Type:	na
Period Type:	duration