Note 4 - Fair Value of Financial Instruments Rollforward of Level III Assets and Liabilities Fair Value Disclosure (Details) (Fair Value, Measurements, Recurring, USD $)	3 Months Ended				9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013
Fair Value Level III Assets and Liabilities [Roll Forward]
Fair Value, Transfers Between Level 1 And Level 2, Amount	$ 0		$ 0		$ 0		$ 0
Derivative liabilities net [Member] | Fair Value, Inputs, Level 3
Fair Value Level III Assets and Liabilities [Roll Forward]
Beginning Balance Level III Liabilities	193,800,000		343,600,000		300,900,000		254,900,000
Realized and Unrealized Gains (Losses) Included in Earnings Level III Liabilities	18,500,000	[1]	11,400,000	[2]	129,000,000	[3]	(69,700,000)	[4]
Realized and unrealized gains (losses) included in OCI	0		0		0		0
Purchases Level III Liabilities	0		0		0		0
Sales Level III Liabilities	0		0		0		0
Issuances Level III Liabilities	0		0		0		0
Settlements Level III Liabilities	(3,900,000)		(5,300,000)		(7,300,000)		(12,900,000)
Transfers Into (Out of) Level III Liabilities	0	[5]	0	[5]	0	[5]	0	[5]
Ending Balance Level III Liabilities	179,200,000		337,500,000		179,200,000		337,500,000
VIE debt | Fair Value, Inputs, Level 3
Fair Value Level III Assets and Liabilities [Roll Forward]
Beginning Balance Level III Liabilities	93,600,000		106,800,000		94,600,000		108,900,000
Realized and Unrealized Gains (Losses) Included in Earnings Level III Liabilities	(1,600,000)	[1]	(1,800,000)	[2]	(8,900,000)	[3]	(9,000,000)	[4]
Realized and unrealized gains (losses) included in OCI	0		0		0		0
Purchases Level III Liabilities	0		0		0		0
Sales Level III Liabilities	0		0		0		0
Issuances Level III Liabilities	0		0		0		0
Settlements Level III Liabilities	4,000,000		4,400,000		12,300,000		13,700,000
Transfers Into (Out of) Level III Liabilities	0	[5]	0	[5]	0	[5]	0	[5]
Ending Balance Level III Liabilities	91,200,000		104,200,000		91,200,000		104,200,000
Unrealized Gains (Losses) Recorded in Earnings on Level III Liabilities Still Held	(900,000)		(1,000,000)		(6,800,000)		(6,400,000)
Total Level III liabilities net [Member] | Fair Value, Inputs, Level 3
Fair Value Level III Assets and Liabilities [Roll Forward]
Beginning Balance Level III Liabilities	287,400,000		450,400,000		395,500,000		363,800,000
Realized and Unrealized Gains (Losses) Included in Earnings Level III Liabilities	16,900,000	[1]	9,600,000	[2]	120,100,000	[3]	(78,700,000)	[4]
Realized and unrealized gains (losses) included in OCI	0		0		0		0
Purchases Level III Liabilities	0		0		0		0
Sales Level III Liabilities	0		0		0		0
Issuances Level III Liabilities	0		0		0		0
Settlements Level III Liabilities	100,000		(900,000)		5,000,000		800,000
Transfers Into (Out of) Level III Liabilities	0	[5]	0	[5]	0	[5]	0	[5]
Ending Balance Level III Liabilities	270,400,000		441,700,000		270,400,000		441,700,000
Derivative Financial Instruments, Liabilities [Member] | Fair Value, Inputs, Level 3
Fair Value Level III Assets and Liabilities [Roll Forward]
Unrealized Gains (Losses) Recorded in Earnings on Level III Liabilities Still Held	14,400,000		5,900,000		100,800,000		(83,500,000)
State and municipal obligations | Fair Value, Inputs, Level 3
Fair Value Level III Assets and Liabilities [Roll Forward]
Beginning Balance Level III Assets	19,500,000		19,400,000		18,700,000		19,000,000
Realized and Unrealized Gains (Losses) Level III Assets Included in Earnings	500,000	[1]	400,000	[2]	1,300,000	[3]	800,000	[4]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)	0		0		0		0
Purchases Level III Assets	200,000		0		200,000		0
Sales Level III Assets	0		0		0		0
Issuances Level III Assets	0		0		0		0
Settlements Level III Assets	1,400,000		1,400,000		1,400,000		1,400,000
Transfers Into (Out of) Level III Assets	0	[5]	0	[5]	0	[5]	0	[5]
Ending Balance Level III Assets	18,800,000		18,400,000		18,800,000		18,400,000
Corporate Bond and Note Securities [Member] | Fair Value, Inputs, Level 3
Fair Value Level III Assets and Liabilities [Roll Forward]
Beginning Balance Level III Assets							0
Realized and Unrealized Gains (Losses) Level III Assets Included in Earnings							(100,000)	[4]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)							0
Purchases Level III Assets							2,700,000
Sales Level III Assets							0
Issuances Level III Assets							0
Settlements Level III Assets							0
Transfers Into (Out of) Level III Assets							(2,600,000)	[5],[6]
Ending Balance Level III Assets			0				0
CMBS | Fair Value, Inputs, Level 3
Fair Value Level III Assets and Liabilities [Roll Forward]
Beginning Balance Level III Assets							0
Realized and Unrealized Gains (Losses) Level III Assets Included in Earnings							0	[4]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)							0
Purchases Level III Assets							3,100,000
Sales Level III Assets							3,100,000
Issuances Level III Assets							0
Settlements Level III Assets							0
Transfers Into (Out of) Level III Assets							0	[5]
Ending Balance Level III Assets			0				0
Other ABS | Fair Value, Inputs, Level 3
Fair Value Level III Assets and Liabilities [Roll Forward]
Beginning Balance Level III Assets	74,400,000		1,200,000		900,000		1,700,000
Realized and Unrealized Gains (Losses) Level III Assets Included in Earnings	300,000	[1]	0	[2]	400,000	[3]	0	[4]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)	(900,000)		0		(1,000,000)		0
Purchases Level III Assets	0		0		29,200,000		0
Sales Level III Assets	0		0		0		0
Issuances Level III Assets	0		0		0		0
Settlements Level III Assets	0		200,000		400,000		700,000
Transfers Into (Out of) Level III Assets	(73,800,000)	[5],[7]	0	[5]	(29,100,000)	[5],[8]	0	[5]
Ending Balance Level III Assets	0		1,000,000		0		1,000,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3					74,300,000	[5],[8]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3					45,200,000	[5],[8]
Equity securities | Fair Value, Inputs, Level 3
Fair Value Level III Assets and Liabilities [Roll Forward]
Beginning Balance Level III Assets			400,000		400,000		1,000,000
Realized and Unrealized Gains (Losses) Level III Assets Included in Earnings			0	[2]	(400,000)	[3]	0	[4]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)			0		0		0
Purchases Level III Assets			0		0		0
Sales Level III Assets			0		0		600,000
Issuances Level III Assets			0		0		0
Settlements Level III Assets			0		0		0
Transfers Into (Out of) Level III Assets			0	[5]	0	[5]	0	[5]
Ending Balance Level III Assets	0		400,000		0		400,000
Other investments | Fair Value, Inputs, Level 3
Fair Value Level III Assets and Liabilities [Roll Forward]
Beginning Balance Level III Assets	82,800,000		77,400,000		81,500,000		79,000,000
Realized and Unrealized Gains (Losses) Level III Assets Included in Earnings	200,000	[1]	2,300,000	[2]	1,500,000	[3]	400,000	[4]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)	0		0		0		0
Purchases Level III Assets	0		500,000		0		1,300,000
Sales Level III Assets	0		0		0		100,000
Issuances Level III Assets	0		0		0		0
Settlements Level III Assets	100,000		0		100,000		400,000
Transfers Into (Out of) Level III Assets	0	[5]	0	[5]	0	[5]	0	[5]
Ending Balance Level III Assets	82,900,000		80,200,000		82,900,000		80,200,000
Investments | Fair Value, Inputs, Level 3
Fair Value Level III Assets and Liabilities [Roll Forward]
Beginning Balance Level III Assets	176,700,000		98,400,000		101,500,000		100,700,000
Realized and Unrealized Gains (Losses) Level III Assets Included in Earnings	1,000,000	[1]	2,700,000	[2]	2,800,000	[3]	1,100,000	[4]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)	(900,000)		0		(1,000,000)		0
Purchases Level III Assets	200,000		500,000		29,400,000		7,100,000
Sales Level III Assets	0		0		0		3,800,000
Issuances Level III Assets	0		0		0		0
Settlements Level III Assets	1,500,000		1,600,000		1,900,000		2,500,000
Transfers Into (Out of) Level III Assets	(73,800,000)	[5]	0	[5]	(29,100,000)	[5]	(2,600,000)	[5]
Ending Balance Level III Assets	101,700,000		100,000,000		101,700,000		100,000,000
Unrealized Gains (Losses) Recorded in Earnings on Level III Assets Still Held	(300,000)		2,300,000		100,000		400,000
NIMS derivative assets | Fair Value, Inputs, Level 3
Fair Value Level III Assets and Liabilities [Roll Forward]
Beginning Balance Level III Assets			1,600,000				1,600,000
Realized and Unrealized Gains (Losses) Level III Assets Included in Earnings			0	[2]			0	[4]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)			0				0
Purchases Level III Assets			0				0
Sales Level III Assets			0				0
Issuances Level III Assets			0				0
Settlements Level III Assets			0				0
Transfers Into (Out of) Level III Assets			0	[5]			0	[5]
Ending Balance Level III Assets			1,600,000				1,600,000
Other Assets Excluding NIMS Derivative Assets [Member] | Fair Value, Inputs, Level 3
Fair Value Level III Assets and Liabilities [Roll Forward]
Beginning Balance Level III Assets	90,400,000		96,000,000		91,900,000		99,200,000
Realized and Unrealized Gains (Losses) Level III Assets Included in Earnings	2,600,000	[1]	2,700,000	[2]	11,500,000	[3]	11,100,000	[4]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)	0		0		0		0
Purchases Level III Assets	0		0		0		0
Sales Level III Assets	0		0		0		0
Issuances Level III Assets	0		0		0		0
Settlements Level III Assets	4,900,000		5,500,000		15,300,000		17,100,000
Transfers Into (Out of) Level III Assets	0	[5]	0	[5]	0	[5]	0	[5]
Ending Balance Level III Assets	88,100,000		93,200,000		88,100,000		93,200,000
Unrealized Gains (Losses) Recorded in Earnings on Level III Assets Still Held	600,000		500,000		5,300,000		3,900,000
Total Level III Assets | Fair Value, Inputs, Level 3
Fair Value Level III Assets and Liabilities [Roll Forward]
Beginning Balance Level III Assets	267,100,000		196,000,000		193,400,000		201,500,000
Realized and Unrealized Gains (Losses) Level III Assets Included in Earnings	3,600,000	[1]	5,400,000	[2]	14,300,000	[3]	12,200,000	[4]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)	(900,000)		0		(1,000,000)		0
Purchases Level III Assets	200,000		500,000		29,400,000		7,100,000
Sales Level III Assets	0		0		0		3,800,000
Issuances Level III Assets	0		0		0		0
Settlements Level III Assets	6,400,000		7,100,000		17,200,000		19,600,000
Transfers Into (Out of) Level III Assets	(73,800,000)	[5]	0	[5]	(29,100,000)	[5]	(2,600,000)	[5]
Ending Balance Level III Assets	$ 189,800,000		$ 194,800,000		$ 189,800,000		$ 194,800,000

[1] Includes unrealized gains (losses) for the three months ended September 30, 2014, relating to assets and liabilities still held as of September 30, 2014 as follows: $(0.3) million for investments, $0.6 million for other assets, $14.4 million for derivative liabilities and $(0.9) million for VIE debt.

[2] Includes unrealized gains (losses) for the three months ended September 30, 2013, relating to assets and liabilities still held as of September 30, 2013 as follows: $2.3 million for investments, $0.5 million for other assets, $5.9 million for derivative liabilities and $(1.0) million for VIE debt.

[3] Includes unrealized gains (losses) for the nine months ended September 30, 2014, relating to assets and liabilities still held as of September 30, 2014 as follows: $0.1 million for investments, $5.3 million for other assets, $100.8 million for derivative liabilities and $(6.8) million for VIE debt.

[4] Includes unrealized gains (losses) for the nine months ended September 30, 2013, relating to assets and liabilities still held at September 30, 2013 as follows: $0.4 million for investments, $3.9 million for other assets, $(83.5) million for derivative liabilities and $(6.4) million for VIE debt.

[5] Transfers are recognized at the end of the period as the availability of market observed inputs changes from period to period.

[6] During the period, pricing from a third-party pricing source became available that utilized observable inputs for individual instruments. As a result, these instruments were transferred out of Level III and into Level II.

[7] During the period, certain securities previously classified in Level III were transferred to Level II as third-party pricing became available.

[8] During the period, $74.3 million of other ABS securities were transferred from Level III to Level II, as third-party pricing became available. We also transferred $45.2 million of other ABS securities previously classified as Level II to Level III, as the pricing inputs were no longer considered observable.