Note 6 - Investments Investments Trading Securities (Details) (USD $)				9 Months Ended	12 Months Ended
	Sep. 30, 2013	Dec. 31, 2012	Aug. 30, 2013 Primary Mortgage Product [Member] 2013 Freddie Mac Agreement [Member] Mortgage Insurance Segment First Lien Position [Member]	Sep. 30, 2013 Securities (Assets)	Dec. 31, 2012 Securities (Assets)	Sep. 30, 2013 US government and agency securities	Dec. 31, 2012 US government and agency securities	Sep. 30, 2013 State and municipal obligations	Dec. 31, 2012 State and municipal obligations	Sep. 30, 2013 Corporate bonds and notes	Dec. 31, 2012 Corporate bonds and notes	Sep. 30, 2013 RMBS	Dec. 31, 2012 RMBS	Sep. 30, 2013 CMBS	Dec. 31, 2012 CMBS	Sep. 30, 2013 Other ABS	Dec. 31, 2012 Other ABS	Sep. 30, 2013 Foreign government securities		Dec. 31, 2012 Foreign government securities		Sep. 30, 2013 Hybrid Instrument [Member]	Dec. 31, 2012 Hybrid Instrument [Member]	Sep. 30, 2013 Equity securities	Dec. 31, 2012 Equity securities	Sep. 30, 2013 Other investments	Dec. 31, 2012 Other investments
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading Securities	$ 3,250,934,000	$ 4,094,622,000				$ 413,169,000	$ 428,519,000	$ 623,899,000	$ 669,975,000	$ 1,097,034,000	$ 1,357,175,000	$ 528,103,000	$ 663,307,000	$ 294,752,000	$ 237,294,000	$ 204,187,000	$ 254,102,000	$ 0	[1]	$ 117,686,000	[1]	$ 417,000	$ 211,944,000	$ 88,435,000	$ 153,722,000	$ 938,000	$ 898,000
Trading Securities, Change in Unrealized Holding (Loss) Gain				(144,600,000)	29,800,000
Restricted Investments Held as Collateral for Master Transaction Agreement			$ 205,000,000

[1] As of September 30, 2013, there were no foreign government securities in our investment portfolio. We sold our investment in foreign government securities during the first quarter of 2013, as our market view of these investments changed, and their performance did not meet our expectations.