Note 5 - Income (Loss) Per Common Share (Details Textual) - $ / shares	3 Months Ended	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
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		398,527,459		395,286,875
Treasury Stock, Shares		4,429,844		3,941,210
Common Stock, Shares, Outstanding		398,527,459		395,286,875
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number		0
Class of Warrant or Right, Outstanding		0
Restricted Stock Units (RSUs) [Member]
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements	3,515,356	3,619,975	3,515,356
Deferred Shares [Member]
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements	635,602	1,352,470	635,602