Note 5 - VIEs NIMS VIEs (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended			9 Months Ended
	Sep. 30, 2013		Sep. 30, 2012	Sep. 30, 2013		Sep. 30, 2012	Dec. 31, 2012
Balance Sheet Related Disclosures
Derivative assets	$ 20,844			$ 20,844			$ 13,609
VIE debt—at fair value	104,218			104,218			108,858
Statement of Operations
Net investment income	26,732		25,635	81,220		91,225
Change in fair value of derivative instruments	10,778		(41,056)	(70,357)		(146,937)
Net gains (losses) on other financial instruments	902		(740)	(3,585)		(80,454)
NIMS VIEs [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Balance Sheet Related Disclosures
Derivative assets	1,577			1,577			1,585
VIE debt—at fair value	11,109			11,109			9,875
Maximum exposure (1)	14,061	[1]		14,061	[1]		14,061	[1]
Statement of Operations
Net investment income				178		427
Change in fair value of derivative instruments				0		3
Net gains (losses) on other financial instruments				(1,270)		(4,500)
NIMS VIEs Additional Disclosures
Number Of Remaining NIMS Bonds	2			2
Net cash inflow				$ 149		$ 4,301

[1] The difference between the carrying amounts of the net asset/liability position and maximum exposure related to VIEs is primarily due to the difference between the face amount of the obligation and the recorded fair values, which include an adjustment for our non-performance risk, as applicable. For those VIEs that have recourse to our general credit, the maximum exposure is based on the net par amount of our insured obligation. For any VIEs that do not have recourse to our general credit, the maximum exposure is generally based on the recorded net assets of the VIE, as of the reporting date.