Represents the number of issuers of loans related to the aggregate allowance on impaired loans.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ Details

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Namespace Prefix:	us-gaap
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=6965416&loc=d3e5111-111524

-Subparagraph (d)

+ Details

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Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The average recorded investment related to impaired financing receivables.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-URI http://asc.fasb.org/extlink&oid=6965416&loc=d3e5212-111524

-Subparagraph (c)(1)

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=6965416&loc=d3e5258-111524

+ Details

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Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The interest income recognized during the time within that period that the financing receivables were impaired.

+ References

+ Details

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Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The interest income recognized on a cash-basis method of accounting during the time within that period that the financing receivables were impaired.

+ References

+ Details

Name:	us-gaap_ImpairedFinancingReceivableInterestIncomeCashBasisMethod
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The recorded investment related to impaired financing receivables.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 14A

-URI http://asc.fasb.org/extlink&oid=6965416&loc=SL6953550-111524

-Subparagraph (b)

+ Details

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Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of allowance for credit losses related to recorded investment.

+ References

+ Details

Name:	us-gaap_ImpairedFinancingReceivableRelatedAllowance
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The unpaid principal balance related to impaired financing receivables.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (a)(4)

-URI http://asc.fasb.org/extlink&oid=6965416&loc=d3e5212-111524

+ Details

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Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Corporate Loans and Allowance for Loan Losses (Details 3) (USD $)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2011 approach issuer component	Sep. 30, 2010	Sep. 30, 2011 month grade day approach issuer component	Sep. 30, 2010	Dec. 31, 2010 issuer
Recorded investment in impaired loans and related allowances for credit losses
Number of issuers of loans related to the aggregate allowance on impaired loans	5		5		5
Recorded Investment	$ 69,420,000		$ 69,420,000		$ 149,785,000
Unpaid Principal Balance	84,443,000		84,443,000		225,592,000
Related Allowance	28,474,000		28,474,000		50,112,000
Average Recorded Investment	62,982,000		83,048,000		145,887,000
Interest Income Recognized	633,000		1,672,000		11,109,000
Recorded investment with nonaccrual status	171,300,000		171,300,000		165,100,000
Interest income recognized using cash basis method	4,000,000	4,100,000	9,700,000	11,100,000
With no related allowance recorded
Recorded investment in impaired loans and related allowances for credit losses
Recorded Investment					16,219,000
Unpaid Principal Balance					83,215,000
Average Recorded Investment			4,055,000		12,873,000
Interest Income Recognized					2,853,000
With an allowance recorded
Recorded investment in impaired loans and related allowances for credit losses
Recorded Investment	69,420,000		69,420,000		133,566,000
Unpaid Principal Balance	84,443,000		84,443,000		142,377,000
Related Allowance	28,474,000		28,474,000		50,112,000
Average Recorded Investment	62,982,000		78,993,000		133,014,000
Interest Income Recognized	633,000		1,672,000		8,256,000
Corporate Loans Held for Investment
Recorded investment in impaired loans and related allowances for credit losses
Recorded investment with nonaccrual status	69,400,000		69,400,000		149,800,000
Interest income recognized using cash basis method	600,000		1,700,000
Corporate Loans Held for Sale
Recorded investment in impaired loans and related allowances for credit losses
Recorded investment with nonaccrual status	101,900,000		101,900,000		15,300,000
Interest income recognized using cash basis method	$ 3,400,000		$ 8,000,000