Note 15 - Stockholders' Equity (Details Textual) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	6 Months Ended
Jun. 30, 2019	Dec. 31, 2018	Feb. 28, 2018
Common Stock, Par or Stated Value Per Share	$ 1	$ 1
Share Repurchase Program [Member]
Common Stock, Par or Stated Value Per Share			$ 0.01
Stock Repurchase Program, Authorized Amount			$ 300.0
Stock Repurchased During Period, Shares	0
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 224.9

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Balance Type:	na
Period Type:	duration