This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258

+ Details

Name:	us-gaap_AssetsFairValueDisclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Fair values as of the balance sheet date of all assets resulting from contracts that meet the criteria of being accounted for as derivative instruments, net of the effects of master netting arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 45

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FIN39-1

-Paragraph 10A, 10B

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 10

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=7491637&loc=d3e13433-108611

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 4, 17

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 45

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 15

-URI http://asc.fasb.org/extlink&oid=7491637&loc=d3e13495-108611

+ Details

Name:	us-gaap_DerivativeAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Fair values as of the balance sheet date of all liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments, net of the effects of master netting arrangements.

+ References

+ Details

Name:	us-gaap_DerivativeLiabilities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of subordinated debt obligations (also known as subordinated loan, subordinated bond, subordinated debenture or junior debt) which has a priority ranking after other debts in a dissolution, measured at fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-Subparagraph a

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a),(b)

-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258

+ Details

Name:	us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisSubordinatedDebtObligations
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

This element represents the aggregate of the liabilities reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

+ References

+ Details

Name:	us-gaap_LiabilitiesFairValueDisclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	us-gaap_LiabilitiesFairValueDisclosureAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Total debt and equity financial instruments including: (1) securities held-to-maturity, (2) trading securities, and (3) securities available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27161-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 19

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.4)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 5

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27232-111563

+ Details

Name:	us-gaap_MarketableSecurities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents notes payable as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 2, 4

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19,20,22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_NotesPayableFairValueDisclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	us-gaap_TradingSecuritiesAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Fair Value of Financial Instruments (Details1) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Aggregate notional amount and estimated net fair value of derivative instruments
Marketable Securities	$ 657,783	$ 647,461
Derivative assets	1,048
Total assets	658,831
Liabilities:
Junior subordinated notes, at fair value	22,450
CDO notes payable, at fair value	159,077
Derivative liabilities	167,155	181,499
Total liabilities	348,682
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Aggregate notional amount and estimated net fair value of derivative instruments
Derivative assets	0
Total assets	0
Liabilities:
Junior subordinated notes, at fair value	0
CDO notes payable, at fair value	0
Derivative liabilities	0
Total liabilities	0
Significant Other Observable Inputs (Level 2) [Member]
Aggregate notional amount and estimated net fair value of derivative instruments
Derivative assets	1,048
Total assets	82,153
Liabilities:
Junior subordinated notes, at fair value	0
CDO notes payable, at fair value	0
Derivative liabilities	83,641
Total liabilities	83,641
Significant Unobservable (Level 3) [Member]
Aggregate notional amount and estimated net fair value of derivative instruments
Derivative assets	0
Total assets	576,678
Liabilities:
Junior subordinated notes, at fair value	22,450
CDO notes payable, at fair value	159,077
Derivative liabilities	83,514
Total liabilities	265,041
Trading securities [Member]
Aggregate notional amount and estimated net fair value of derivative instruments
Marketable Securities	490,170
Trading securities [Member] \| TruPS [Member]
Aggregate notional amount and estimated net fair value of derivative instruments
Marketable Securities	490,170
Trading securities [Member] \| Other Securities [Member]
Aggregate notional amount and estimated net fair value of derivative instruments
Marketable Securities	0
Trading securities [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| TruPS [Member]
Aggregate notional amount and estimated net fair value of derivative instruments
Marketable Securities	0
Trading securities [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| Other Securities [Member]
Aggregate notional amount and estimated net fair value of derivative instruments
Marketable Securities	0
Trading securities [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| TruPS [Member]
Aggregate notional amount and estimated net fair value of derivative instruments
Marketable Securities	0
Trading securities [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Other Securities [Member]
Aggregate notional amount and estimated net fair value of derivative instruments
Marketable Securities	0
Trading securities [Member] \| Significant Unobservable (Level 3) [Member] \| TruPS [Member]
Aggregate notional amount and estimated net fair value of derivative instruments
Marketable Securities	490,170
Trading securities [Member] \| Significant Unobservable (Level 3) [Member] \| Other Securities [Member]
Aggregate notional amount and estimated net fair value of derivative instruments
Marketable Securities	0
Security-related receivables [Member] \| TruPS Receivables [Member]
Aggregate notional amount and estimated net fair value of derivative instruments
Marketable Securities	86,508
Security-related receivables [Member] \| Unsecured REIT note receivables [Member]
Aggregate notional amount and estimated net fair value of derivative instruments
Marketable Securities	31,697
Security-related receivables [Member] \| CMBS receivables [Member]
Aggregate notional amount and estimated net fair value of derivative instruments
Marketable Securities	39,300
Security-related receivables [Member] \| Other securities [Member]
Aggregate notional amount and estimated net fair value of derivative instruments
Marketable Securities	10,106
Security-related receivables [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| TruPS Receivables [Member]
Aggregate notional amount and estimated net fair value of derivative instruments
Marketable Securities	0
Security-related receivables [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| Unsecured REIT note receivables [Member]
Aggregate notional amount and estimated net fair value of derivative instruments
Marketable Securities	0
Security-related receivables [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| CMBS receivables [Member]
Aggregate notional amount and estimated net fair value of derivative instruments
Marketable Securities	0
Security-related receivables [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| Other securities [Member]
Aggregate notional amount and estimated net fair value of derivative instruments
Marketable Securities	0
Security-related receivables [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| TruPS Receivables [Member]
Aggregate notional amount and estimated net fair value of derivative instruments
Marketable Securities	0
Security-related receivables [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Unsecured REIT note receivables [Member]
Aggregate notional amount and estimated net fair value of derivative instruments
Marketable Securities	31,697
Security-related receivables [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| CMBS receivables [Member]
Aggregate notional amount and estimated net fair value of derivative instruments
Marketable Securities	39,300
Security-related receivables [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Other securities [Member]
Aggregate notional amount and estimated net fair value of derivative instruments
Marketable Securities	10,106
Security-related receivables [Member] \| Significant Unobservable (Level 3) [Member] \| TruPS Receivables [Member]
Aggregate notional amount and estimated net fair value of derivative instruments
Marketable Securities	86,508
Security-related receivables [Member] \| Significant Unobservable (Level 3) [Member] \| Unsecured REIT note receivables [Member]
Aggregate notional amount and estimated net fair value of derivative instruments
Marketable Securities	0
Security-related receivables [Member] \| Significant Unobservable (Level 3) [Member] \| CMBS receivables [Member]
Aggregate notional amount and estimated net fair value of derivative instruments
Marketable Securities	0
Security-related receivables [Member] \| Significant Unobservable (Level 3) [Member] \| Other securities [Member]
Aggregate notional amount and estimated net fair value of derivative instruments
Marketable Securities	0
Available-for-sale securities [Member]
Aggregate notional amount and estimated net fair value of derivative instruments
Marketable Securities	2
Available-for-sale securities [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Aggregate notional amount and estimated net fair value of derivative instruments
Marketable Securities	0
Available-for-sale securities [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Aggregate notional amount and estimated net fair value of derivative instruments
Marketable Securities	2
Available-for-sale securities [Member] \| Significant Unobservable (Level 3) [Member]
Aggregate notional amount and estimated net fair value of derivative instruments
Marketable Securities	$ 0