Note 4 - Financing Arrangements (Details) - Outstanding Borrowings (USD $)	Sep. 30, 2013	Dec. 31, 2012
Note 4 - Financing Arrangements (Details) - Outstanding Borrowings [Line Items]
Less current portion of long-term debt	$ (250,000,000)	$ (100,000,000)
Total long-term debt	437,474,000	585,347,000
Senior Debt Obligations [Member] | Line of Credit [Member]
Note 4 - Financing Arrangements (Details) - Outstanding Borrowings [Line Items]
Senior revolving line of credit	187,800,000	85,800,000
Senior Debt Obligations [Member] | Loans Payable [Member]
Note 4 - Financing Arrangements (Details) - Outstanding Borrowings [Line Items]
Long-term debt	150,000,000	200,000,000
Senior Debt Obligations [Member] | Senior Notes [Member]
Note 4 - Financing Arrangements (Details) - Outstanding Borrowings [Line Items]
Long-term debt	$ 349,700,000	$ 399,500,000