Note 5 - Earnings (Loss) Per Common Share (Details Textual) - $ / shares	3 Months Ended
	Mar. 31, 2017	Dec. 31, 2016
Common Stock, Shares Authorized	500,000,000	500,000,000
Common Stock, Par or Stated Value Per Share	$ 0.25	$ 0.25
Common Stock, Shares, Issued	399,911,009
Treasury Stock, Shares	4,085,599	3,941,210
Common Stock, Shares, Outstanding	395,825,410	395,286,875
Class of Warrant or Right, Outstanding	0
Restricted Stock Units (RSUs) [Member]
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements	2,735,569
Deferred Shares [Member]
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements	727,262