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Note 8 - Stockholders' Equity (Details Textual) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended		9 Months Ended
	Apr. 30, 2019	Apr. 30, 2015	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2011
Stock Repurchase Program, Remaining Authorized Repurchase Amount			$ 0		$ 0
Common Stock, Shares, Outstanding, Ending Balance (in shares)			82,068,638		82,068,638
Share-based Payment Arrangement, Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in shares)			3,700,000	2,500,000	3,800,000	2,500,000
Restricted stock, Restricted Units or Performance Stock Unit Awards [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in shares)			400,000		500,000
2011 Omnibus Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)							3,250,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized (in shares)	2,500,000	4,250,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)					9,553,717
2011 Omnibus Incentive Plan [Member] \| Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)					336,325
2011 Omnibus Incentive Plan [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)					169,603
2011 Omnibus Incentive Plan [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)					1,336,430
2011 Omnibus Incentive Plan [Member] \| Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)					1 year
2011 Omnibus Incentive Plan [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year)					10 years
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)					3 years
2011 Omnibus Incentive Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)					5 years