Fair Value (Schedule Of Fair Value Of Predominantly Bank Trust Preferred CDOs) (Details) (USD $) In Thousands, unless otherwise specified	0 Months Ended
	Sep. 30, 2012
Financing Receivable, Recorded Investment [Line Items]
Fair value of predominantly bank trust preferred CDOs	$ 811,713
Percentage of total fair value by vintage	100.00%
AAA [Member]
Financing Receivable, Recorded Investment [Line Items]
Percentage of total fair value	76.60%
A [Member]
Financing Receivable, Recorded Investment [Line Items]
Percentage of total fair value	23.10%
BBB [Member]
Financing Receivable, Recorded Investment [Line Items]
Percentage of total fair value	0.30%
2001 [Member]
Financing Receivable, Recorded Investment [Line Items]
Fair value of predominantly bank trust preferred CDOs	48,744
Percentage of total fair value by vintage	6.00%
2001 [Member] | AAA [Member]
Financing Receivable, Recorded Investment [Line Items]
Percentage of total fair value	4.80%
2001 [Member] | A [Member]
Financing Receivable, Recorded Investment [Line Items]
Percentage of total fair value	1.10%
2001 [Member] | BBB [Member]
Financing Receivable, Recorded Investment [Line Items]
Percentage of total fair value	0.10%
2002 [Member]
Financing Receivable, Recorded Investment [Line Items]
Fair value of predominantly bank trust preferred CDOs	253,291
Percentage of total fair value by vintage	31.20%
2002 [Member] | AAA [Member]
Financing Receivable, Recorded Investment [Line Items]
Percentage of total fair value	29.30%
2002 [Member] | A [Member]
Financing Receivable, Recorded Investment [Line Items]
Percentage of total fair value	1.90%
2002 [Member] | BBB [Member]
Financing Receivable, Recorded Investment [Line Items]
Percentage of total fair value	0.00%
2003 [Member]
Financing Receivable, Recorded Investment [Line Items]
Fair value of predominantly bank trust preferred CDOs	279,913
Percentage of total fair value by vintage	34.60%
2003 [Member] | AAA [Member]
Financing Receivable, Recorded Investment [Line Items]
Percentage of total fair value	25.40%
2003 [Member] | A [Member]
Financing Receivable, Recorded Investment [Line Items]
Percentage of total fair value	9.20%
2003 [Member] | BBB [Member]
Financing Receivable, Recorded Investment [Line Items]
Percentage of total fair value	0.00%
2004 [Member]
Financing Receivable, Recorded Investment [Line Items]
Fair value of predominantly bank trust preferred CDOs	134,004
Percentage of total fair value by vintage	16.50%
2004 [Member] | AAA [Member]
Financing Receivable, Recorded Investment [Line Items]
Percentage of total fair value	8.40%
2004 [Member] | A [Member]
Financing Receivable, Recorded Investment [Line Items]
Percentage of total fair value	8.10%
2004 [Member] | BBB [Member]
Financing Receivable, Recorded Investment [Line Items]
Percentage of total fair value	0.00%
2005 [Member]
Financing Receivable, Recorded Investment [Line Items]
Fair value of predominantly bank trust preferred CDOs	13,863
Percentage of total fair value by vintage	1.70%
2005 [Member] | AAA [Member]
Financing Receivable, Recorded Investment [Line Items]
Percentage of total fair value	1.00%
2005 [Member] | A [Member]
Financing Receivable, Recorded Investment [Line Items]
Percentage of total fair value	0.70%
2005 [Member] | BBB [Member]
Financing Receivable, Recorded Investment [Line Items]
Percentage of total fair value	0.00%
2006 [Member]
Financing Receivable, Recorded Investment [Line Items]
Fair value of predominantly bank trust preferred CDOs	42,531
Percentage of total fair value by vintage	5.20%
2006 [Member] | AAA [Member]
Financing Receivable, Recorded Investment [Line Items]
Percentage of total fair value	2.90%
2006 [Member] | A [Member]
Financing Receivable, Recorded Investment [Line Items]
Percentage of total fair value	2.10%
2006 [Member] | BBB [Member]
Financing Receivable, Recorded Investment [Line Items]
Percentage of total fair value	0.20%
2007 [Member]
Financing Receivable, Recorded Investment [Line Items]
Fair value of predominantly bank trust preferred CDOs	$ 39,367
Percentage of total fair value by vintage	4.80%
2007 [Member] | AAA [Member]
Financing Receivable, Recorded Investment [Line Items]
Percentage of total fair value	4.80%
2007 [Member] | A [Member]
Financing Receivable, Recorded Investment [Line Items]
Percentage of total fair value	0.00%
2007 [Member] | BBB [Member]
Financing Receivable, Recorded Investment [Line Items]
Percentage of total fair value	0.00%