Contingencies And Other Disclosures (Schedule Of Repurchase Of Investments) (Details) (USD $) In Thousands	Sep. 30, 2011
2005 [Member] | Alt-A Mortgage Loan Pools [Member] | Junior Investor Rank [Member]
Amounts claimed by plaintiffs invested in proprietary securitizations
2006 [Member] | Alt-A Mortgage Loan Pools [Member] | Senior Investor Rank [Member]
Amounts claimed by plaintiffs invested in proprietary securitizations	230,020
2005 [Member] | Alt-A Mortgage Loan Pools [Member] | Senior Investor Rank [Member]
Amounts claimed by plaintiffs invested in proprietary securitizations	643,751
2006 [Member] | Alt-A Mortgage Loan Pools [Member] | Junior Investor Rank [Member]
Amounts claimed by plaintiffs invested in proprietary securitizations
2007 [Member] | Alt-A Mortgage Loan Pools [Member] | Senior Investor Rank [Member]
Amounts claimed by plaintiffs invested in proprietary securitizations	5,050
2007 [Member] | Alt-A Mortgage Loan Pools [Member] | Junior Investor Rank [Member]
Amounts claimed by plaintiffs invested in proprietary securitizations
Alt-A Mortgage Loan Pools [Member] | Senior Investor Rank [Member]
Amounts claimed by plaintiffs invested in proprietary securitizations	878,821
Alt-A Mortgage Loan Pools [Member] | Junior Investor Rank [Member]
Amounts claimed by plaintiffs invested in proprietary securitizations
2006 [Member] | Jumbo [Member] | Senior Investor Rank [Member]
Amounts claimed by plaintiffs invested in proprietary securitizations	84,659
2005 [Member] | Jumbo [Member] | Senior Investor Rank [Member]
Amounts claimed by plaintiffs invested in proprietary securitizations	60,000
2006 [Member] | Jumbo [Member] | Junior Investor Rank [Member]
Amounts claimed by plaintiffs invested in proprietary securitizations	9,793
2007 [Member] | Jumbo [Member] | Senior Investor Rank [Member]
Amounts claimed by plaintiffs invested in proprietary securitizations	50,000
2007 [Member] | Jumbo [Member] | Junior Investor Rank [Member]
Amounts claimed by plaintiffs invested in proprietary securitizations	7,084
Jumbo [Member] | Senior Investor Rank [Member]
Amounts claimed by plaintiffs invested in proprietary securitizations	194,659
Jumbo [Member] | Junior Investor Rank [Member]
Amounts claimed by plaintiffs invested in proprietary securitizations	$ 16,877