Note 6 - VIEs Put Options On CPS (Details) (USD $)	12 Months Ended
	Dec. 31, 2011		Dec. 31, 2010		Dec. 31, 2009	Jun. 30, 2010	Sep. 30, 2003
Balance Sheet Related Disclosures
Short-term Investments	$ 1,261,703,000		$ 1,537,498,000
Statement of Operations
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)
Other operating expenses	175,810,000		191,942,000		203,770,000
Consolidated Committed Preferred Custodial Trust Securities [Member]
Balance Sheet Related Disclosures
Short-term Investments	150,000,000		150,000,000
Maximum exposure (1)	150,000,000	[1]	150,000,000	[1]
Statement of Operations
Net investment income	200,000		0
Change in fair value of derivative instruments, gain (loss)	0		200,000
Net gains (losses) on other financial instruments	0		(25,700,000)
Other operating expenses	400,000		400,000
CPS Additional Disclosure
Number of Committed Preferred Custodial Trusts	3
Net cash inflow (outflow) for VIEs	(200,000)		(83,400,000)
Unconsolidated Committed Preferred Custodial Trust Securities
Statement of Operations
Net investment income	0		0
Change in fair value of derivative instruments, gain (loss)	0		(6,300,000)		(56,200,000)
Net gains (losses) on other financial instruments	0		0
Other operating expenses	0		0
CPS Additional Disclosure
Number of Committed Preferred Custodial Trusts							3
Committed Preferred Custodial Trust Securities							150,000,000
Committed Preferred Custodial Trust Securities Held By Each Trust							50,000,000
Number Of Committed Preferred Custodial Trusts Consolidated During 2009					2
Variable Interest Entity, Initial Consolidation, Gain (Loss)			(13,900,000)
Number Of Committed Preferred Custodial Trusts Not Consolidated Prior To The Second Quarter Of The Prior Year						1
Net cash inflow (outflow) for VIEs	$ 0		$ (900,000)		$ (3,700,000)

[1] The maximum exposure is based on our carrying amounts of the investments.