Note 1 - Description of Business and Basis of Presentation (Restated) (Details Textual) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Defined Benefit Plan, Termination Charge	$ 6,945	$ 0	$ 6,945	$ 0
Income Tax Expense (Benefit), Total	(840)	$ 3,700	1,910	$ 4,950
Deferred Income Tax Assets, Net, Total	447		447		$ 0
Deferred Income Tax Liabilities, Net, Total	0		0		$ 450
Revision of Prior Period, Error Correction, Adjustment [Member]
Income Tax Expense (Benefit), Total	(1,800)		(1,800)
Deferred Income Tax Assets, Net, Total	447		447
Deferred Income Tax Liabilities, Net, Total	(1,353)		(1,353)
Noncontributory Qualified Defined Pension Plans [Member]
Defined Benefit Plan, Termination Charge	$ 6,900		$ 6,900