Note 11 - Earnings Per Share (Details) - Earnings Per Share (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Basic EPS:
Income from continuing operations (in Dollars)	$ 79,009	$ 52,622	$ 50,453
Assumed conversions of Senior Notes (in Dollars)	5,091	5,005	4,771
Adjusted income from continuing operations (in Dollars)	$ 84,100	$ 57,627	$ 55,224
Weighted average number of common shares outstanding - basic	82,999	85,095	87,522
Add: Dilutive effect of stock options and restricted stock awards	1,733	1,767	876
Dilutive effect of Senior Notes	15,682	15,682	15,682
Diluted weighted average number of common shares outstanding	100,414	102,544	104,080
Diluted income from continuing operations per common share (in Dollars per share)	$ 0.84	$ 0.56	$ 0.53
Stock options and restricted stock excluded from calculation of diluted earnings per share because anti-dilutive for the period	788	415	2,671
Basic income from continuing operations per common share (in Dollars per share)	$ 0.95	$ 0.62	$ 0.58

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of convertible debt securities using the if-converted method.

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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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