Note 6 - VIEs NIMS VIEs (Details) (USD $)	12 Months Ended
	Dec. 31, 2011		Dec. 31, 2010		Dec. 31, 2009
Balance Sheet Related Disclosures
Derivative Assets	$ 17,212,000		$ 26,212,000
VIE debt	228,240,000		520,114,000		296,080,000
Statement of Operations
Premiums earned	756,025,000		825,733,000		825,901,000
Net investment income	163,520,000		178,760,000		214,190,000
Change in fair value of derivative instruments, gain (loss)	628,395,000		(558,712,000)		99,958,000
Net gains (losses) on other financial instruments	193,329,000		(211,681,000)		(88,569,000)
NIMS VIEs
Balance Sheet Related Disclosures
Derivative Assets	1,600,000		10,900,000
VIE debt	9,400,000		141,000,000
Maximum exposure (1)	18,500,000	[1]	135,800,000	[1]
Statement of Operations
Premiums earned					800,000
Net investment income	500,000		400,000
Change in fair value of derivative instruments, gain (loss)	(1,600,000)		(900,000)		(6,200,000)
Net gains (losses) on other financial instruments	4,400,000		(39,600,000)		(99,500,000)
NIMS VIEs Additional Disclosures
Net cash inflow (outflow) for VIEs	$ (119,100,000)		$ (187,100,000)		$ (68,100,000)
Number Of NIMS Bonds Purchased
Average Remaining Maturity in Years of Existing NIMS Transactions
Years Left To Maturity Of A Majority Of Our NIMS Transactions	1
Number of NIMS Bonds Not Maturing Within One Year	2

[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 includes an adjustment for our non-performance risk. The maximum exposure is based on the net par amount of our insured obligations as of the reporting date.