Note 5 - Earnings (Loss) Per Common Share (Details Textual) - $ / shares	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Common Stock, Shares Authorized	750,000,000		750,000,000
Common Stock, Par or Stated Value Per Share	$ 0.25		$ 0.25
Common Stock, Shares, Issued, Total	400,301,617		399,176,425
Treasury Stock, Shares, Ending Balance	4,864,799		4,529,450
Common Stock, Shares, Outstanding, Ending Balance	400,301,617		399,176,425
Earnings Per Share, Basic and Diluted, Total	$ 0.02	$ 0.07
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number, Ending Balance			0
Class of Warrant or Right, Outstanding			0
Restricted Stock Units (RSUs) [Member]
Incremental Common Shares Attributable to Share-based Payment Arrangements, Total	1,092,307	2,051,734
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	539,204
Deferred Shares [Member]
Incremental Common Shares Attributable to Share-based Payment Arrangements, Total	1,509,159	727,262
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	212,602

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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Number of warrants or rights outstanding.

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Face amount or stated value per share of common stock.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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