Note 9 - Financing Arrangements, Portfolio Investments (Details) - Outstanding Repurchase Agreement Borrowings by Contractual Maturity (USD $)
In Thousands, unless otherwise specified
Dec. 31, 2013
Dec. 31, 2012
Note 9 - Financing Arrangements, Portfolio Investments (Details) - Outstanding Repurchase Agreement Borrowings by Contractual Maturity [Line Items]    
Outstanding repurchase agreement by contractual maturity $ 791,125 $ 889,134
Maturity up to 30 days [Member]
   
Note 9 - Financing Arrangements, Portfolio Investments (Details) - Outstanding Repurchase Agreement Borrowings by Contractual Maturity [Line Items]    
Outstanding repurchase agreement by contractual maturity 509,564 765,593
Maturity 30 to 90 Days [Member]
   
Note 9 - Financing Arrangements, Portfolio Investments (Details) - Outstanding Repurchase Agreement Borrowings by Contractual Maturity [Line Items]    
Outstanding repurchase agreement by contractual maturity $ 281,561 $ 123,541