Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Note 12 - Stock Compensation Plans (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	May 23, 2017	Apr. 25, 2012	May 17, 2011
Share-based Payment Arrangement, Expense	$ 1,400,000	$ 2,100,000	$ 2,300,000
Stock Options [Member]
Share-based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value	383,000	$ 120,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares (in shares)		0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	87,000	$ 76,000	$ 2,900,000
Restricted Stock Units (RSUs) [Member]
Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount	$ 500,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)	6 months
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)	$ 5.95	$ 5.84	$ 6.53
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value	$ 1,000,000.0	$ 1,600,000	$ 2,900,000
Restricted Stock Units (RSUs) [Member] \| Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)	1 year
The 2010 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)				8,500,000	4,500,000	2,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year)	10 years