Note 14 - Federal and State Income Taxes - Federal and State Income Tax Expense (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Federal and State Income Taxes
Current									$ 8,255	$ 2,723	$ 10,976
Deferred									6,364	6,292	(6,030)
Federal and state income tax expense	$ 6,560	$ 3,573	$ 3,073	$ 1,413	$ 3,535	$ 1,608	$ 1,881	$ 1,991	$ 14,619	$ 9,015	$ 4,946

Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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