Investment Securities (Securities With Other-Than-Temporary Impairment) (Details) (USD $) In Thousands	3 Months Ended		9 Months Ended		12 Months Ended		3 Months Ended		9 Months Ended			3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended				9 Months Ended				3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended				9 Months Ended				3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended	9 Months Ended	12 Months Ended		9 Months Ended		12 Months Ended		9 Months Ended		12 Months Ended		9 Months Ended		12 Months Ended		9 Months Ended		12 Months Ended				9 Months Ended		12 Months Ended		9 Months Ended		12 Months Ended		9 Months Ended		12 Months Ended		9 Months Ended		12 Months Ended				9 Months Ended		12 Months Ended		9 Months Ended		12 Months Ended				9 Months Ended		12 Months Ended		3 Months Ended	9 Months Ended				3 Months Ended		9 Months Ended				3 Months Ended		9 Months Ended				12 Months Ended		9 Months Ended	12 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010	Dec. 31, 2009	Sep. 30, 2011 Mortgage-Backed Securities - Non-Agency Group 1 [Member]	Sep. 30, 2010 Mortgage-Backed Securities - Non-Agency Group 1 [Member]	Sep. 30, 2011 Mortgage-Backed Securities - Non-Agency Group 1 [Member]	Sep. 30, 2010 Mortgage-Backed Securities - Non-Agency Group 1 [Member]	Dec. 31, 2010 Mortgage-Backed Securities - Non-Agency Group 1 [Member]	Sep. 30, 2010 Mortgage-Backed Securities - Non-Agency Group 1 [Member] BAFC Ser 4 [Member]		Sep. 30, 2010 Mortgage-Backed Securities - Non-Agency Group 1 [Member] BAFC Ser 4 [Member]		Sep. 30, 2010 Mortgage-Backed Securities - Non-Agency Group 1 [Member] CWALT Ser 73CB 1 [Member]		Sep. 30, 2010 Mortgage-Backed Securities - Non-Agency Group 1 [Member] CWALT Ser 73CB 1 [Member]		Sep. 30, 2010 Mortgage-Backed Securities - Non-Agency Group 1 [Member] CWALT Ser 73CB 2 [Member]		Sep. 30, 2010 Mortgage-Backed Securities - Non-Agency Group 1 [Member] CWALT Ser 73CB 2 [Member]		Sep. 30, 2010 Mortgage-Backed Securities - Non-Agency Group 1 [Member] CWHL 2006-10 [Member]		Sep. 30, 2010 Mortgage-Backed Securities - Non-Agency Group 1 [Member] CWHL 2006-10 [Member]		Sep. 30, 2010 Mortgage-Backed Securities - Non-Agency Group 1 [Member] CWHL 2005-20 [Member]		Sep. 30, 2010 Mortgage-Backed Securities - Non-Agency Group 1 [Member] CWHL 2005-20 [Member]		Sep. 30, 2011 Mortgage-Backed Securities - Non-Agency Group 1 [Member] FHASI Ser 4 [Member]		Sep. 30, 2010 Mortgage-Backed Securities - Non-Agency Group 1 [Member] FHASI Ser 4 [Member]		Sep. 30, 2011 Mortgage-Backed Securities - Non-Agency Group 1 [Member] FHASI Ser 4 [Member]		Sep. 30, 2010 Mortgage-Backed Securities - Non-Agency Group 1 [Member] FHASI Ser 4 [Member]		Sep. 30, 2011 Mortgage-Backed Securities - Non-Agency Group 1 [Member] HALO Ser 1R [Member]		Sep. 30, 2011 Mortgage-Backed Securities - Non-Agency Group 1 [Member] HALO Ser 1R [Member]		Sep. 30, 2010 Mortgage-Backed Securities - Non-Agency Group 1 [Member] RFMSI Ser S9 [Member]		Sep. 30, 2010 Mortgage-Backed Securities - Non-Agency Group 1 [Member] RFMSI Ser S9 [Member]		Sep. 30, 2011 Mortgage-Backed Securities - Non-Agency Group 1 [Member] RFMSI Ser S10 [Member]		Sep. 30, 2010 Mortgage-Backed Securities - Non-Agency Group 1 [Member] RFMSI Ser S10 [Member]		Sep. 30, 2011 Mortgage-Backed Securities - Non-Agency Group 1 [Member] RFMSI Ser S10 [Member]		Sep. 30, 2010 Mortgage-Backed Securities - Non-Agency Group 1 [Member] RFMSI Ser S10 [Member]		Sep. 30, 2010 Mortgage-Backed Securities - Non-Agency Group 1 [Member] RALI QS2 [Member]		Sep. 30, 2010 Mortgage-Backed Securities - Non-Agency Group 1 [Member] RALI QS2 [Member]		Sep. 30, 2010 Mortgage-Backed Securities - Non-Agency Group 1 [Member] RFMSI S1 [Member]		Sep. 30, 2010 Mortgage-Backed Securities - Non-Agency Group 1 [Member] RFMSI S1 [Member]		Sep. 30, 2011 Mortgage-Backed Securities - Non-Agency Group 2 [Member]	Sep. 30, 2011 Mortgage-Backed Securities - Non-Agency Group 2 [Member]	Dec. 31, 2010 Mortgage-Backed Securities - Non-Agency Group 2 [Member]	Dec. 31, 2009 Mortgage-Backed Securities - Non-Agency Group 2 [Member]	Sep. 30, 2011 Mortgage-Backed Securities - Non-Agency Group 2 [Member] BAFC Ser 4 [Member]		Dec. 31, 2010 Mortgage-Backed Securities - Non-Agency Group 2 [Member] BAFC Ser 4 [Member]	Dec. 31, 2009 Mortgage-Backed Securities - Non-Agency Group 2 [Member] BAFC Ser 4 [Member]	Sep. 30, 2011 Mortgage-Backed Securities - Non-Agency Group 2 [Member] CWALT Ser 73CB 1 [Member]		Dec. 31, 2010 Mortgage-Backed Securities - Non-Agency Group 2 [Member] CWALT Ser 73CB 1 [Member]	Dec. 31, 2009 Mortgage-Backed Securities - Non-Agency Group 2 [Member] CWALT Ser 73CB 1 [Member]	Sep. 30, 2011 Mortgage-Backed Securities - Non-Agency Group 2 [Member] CWALT Ser 73CB 2 [Member]		Dec. 31, 2010 Mortgage-Backed Securities - Non-Agency Group 2 [Member] CWALT Ser 73CB 2 [Member]	Dec. 31, 2009 Mortgage-Backed Securities - Non-Agency Group 2 [Member] CWALT Ser 73CB 2 [Member]	Sep. 30, 2011 Mortgage-Backed Securities - Non-Agency Group 2 [Member] CWHL 2006-10 [Member]		Dec. 31, 2010 Mortgage-Backed Securities - Non-Agency Group 2 [Member] CWHL 2006-10 [Member]		Dec. 31, 2009 Mortgage-Backed Securities - Non-Agency Group 2 [Member] CWHL 2006-10 [Member]		Sep. 30, 2011 Mortgage-Backed Securities - Non-Agency Group 2 [Member] CWHL 2005-20 [Member]		Dec. 31, 2010 Mortgage-Backed Securities - Non-Agency Group 2 [Member] CWHL 2005-20 [Member]	Dec. 31, 2009 Mortgage-Backed Securities - Non-Agency Group 2 [Member] CWHL 2005-20 [Member]	Sep. 30, 2011 Mortgage-Backed Securities - Non-Agency Group 2 [Member] FHASI Ser 4 [Member]		Dec. 31, 2010 Mortgage-Backed Securities - Non-Agency Group 2 [Member] FHASI Ser 4 [Member]	Dec. 31, 2009 Mortgage-Backed Securities - Non-Agency Group 2 [Member] FHASI Ser 4 [Member]	Sep. 30, 2011 Mortgage-Backed Securities - Non-Agency Group 2 [Member] HALO Ser 1R [Member]		Dec. 31, 2010 Mortgage-Backed Securities - Non-Agency Group 2 [Member] HALO Ser 1R [Member]	Dec. 31, 2009 Mortgage-Backed Securities - Non-Agency Group 2 [Member] HALO Ser 1R [Member]	Sep. 30, 2011 Mortgage-Backed Securities - Non-Agency Group 2 [Member] RFMSI Ser S9 [Member]		Dec. 31, 2010 Mortgage-Backed Securities - Non-Agency Group 2 [Member] RFMSI Ser S9 [Member]		Dec. 31, 2009 Mortgage-Backed Securities - Non-Agency Group 2 [Member] RFMSI Ser S9 [Member]		Sep. 30, 2011 Mortgage-Backed Securities - Non-Agency Group 2 [Member] RFMSI Ser S10 [Member]		Dec. 31, 2010 Mortgage-Backed Securities - Non-Agency Group 2 [Member] RFMSI Ser S10 [Member]	Dec. 31, 2009 Mortgage-Backed Securities - Non-Agency Group 2 [Member] RFMSI Ser S10 [Member]	Sep. 30, 2011 Mortgage-Backed Securities - Non-Agency Group 2 [Member] RALI QS2 [Member]		Dec. 31, 2010 Mortgage-Backed Securities - Non-Agency Group 2 [Member] RALI QS2 [Member]		Dec. 31, 2009 Mortgage-Backed Securities - Non-Agency Group 2 [Member] RALI QS2 [Member]		Sep. 30, 2011 Mortgage-Backed Securities - Non-Agency Group 2 [Member] RFMSI S1 [Member]		Dec. 31, 2010 Mortgage-Backed Securities - Non-Agency Group 2 [Member] RFMSI S1 [Member]	Dec. 31, 2009 Mortgage-Backed Securities - Non-Agency Group 2 [Member] RFMSI S1 [Member]	Sep. 30, 2010 Pooled Trust Preferred Securities Group 1 [Member]	Sep. 30, 2010 Pooled Trust Preferred Securities Group 1 [Member]	Sep. 30, 2011 Pooled Trust Preferred Securities Group 1 [Member]	Jun. 30, 2011 Pooled Trust Preferred Securities Group 1 [Member]	Dec. 31, 2010 Pooled Trust Preferred Securities Group 1 [Member]	Sep. 30, 2010 Pooled Trust Preferred Securities Group 1 [Member] MM Community Funding IX [Member]		Sep. 30, 2010 Pooled Trust Preferred Securities Group 1 [Member] MM Community Funding IX [Member]		Sep. 30, 2011 Pooled Trust Preferred Securities Group 1 [Member] MM Community Funding IX [Member]		Sep. 30, 2010 Pooled Trust Preferred Securities Group 1 [Member] TROPC [Member]		Sep. 30, 2010 Pooled Trust Preferred Securities Group 1 [Member] TROPC [Member]		Sep. 30, 2011 MM Community Funding IX [Member] Pooled Trust Preferred Securities Group 2 [Member]		Dec. 31, 2010 MM Community Funding IX [Member] Pooled Trust Preferred Securities Group 2 [Member]	Dec. 31, 2009 MM Community Funding IX [Member] Pooled Trust Preferred Securities Group 2 [Member]	Sep. 30, 2011 Pooled Trust Preferred Securities Group 2 [Member]	Dec. 31, 2010 Pooled Trust Preferred Securities Group 2 [Member]	Dec. 31, 2009 Pooled Trust Preferred Securities Group 2 [Member]	Sep. 30, 2011 Pooled Trust Preferred Securities Group 2 [Member] TROPC [Member]		Dec. 31, 2010 Pooled Trust Preferred Securities Group 2 [Member] TROPC [Member]	Dec. 31, 2009 Pooled Trust Preferred Securities Group 2 [Member] TROPC [Member]
Vintage														2007				2005				2005				2006				2005						2007		2007				2006				2006						2006		2006				2006				2006						2007				2005				2005				2006	[1]					2005				2007				2006				2006	[2]					2006				2006	[2]					2006											2003						2003		2003							2003
Lowest Credit Rating												CCC	[3]	CCC	[3]	CCC	[3]	CCC	[3]	CCC	[3]	CCC	[3]	C	[3]	C	[3]	B-	[3]	B-	[3]	CC	[3]	CCC	[3]	CC	[3]	CCC	[3]	B	[3]	B	[3]	CC	[3]	CC	[3]	CC	[3]	CC	[3]	CC	[3]	CC	[3]	C	[3]	C	[3]	CCC	[3]	CCC	[3]					CCC	[3]			CC	[3]			CC	[3]									CC	[3]			CC	[3]			B	[3]									CC	[3]									CCC	[3]								C	[3]	C	[3]	D	[3]	C	[3]	C	[3]	D	[3]						C	[3]
Amortized Cost	$ 2,205,285		$ 2,205,285		$ 1,953,842		$ 39,860	$ 117,058	$ 39,860	$ 117,058	$ 134,168	$ 14,026		$ 14,026		$ 6,606		$ 6,606		$ 6,923		$ 6,923		$ 10,030		$ 10,030		$ 9,734		$ 9,734		$ 20,003		$ 21,617		$ 20,003		$ 21,617		$ 15,640		$ 15,640		$ 32,070		$ 32,070		$ 4,217		$ 4,360		$ 4,217		$ 4,360		$ 6,565		$ 6,565		$ 5,127		$ 5,127		$ 70,653	$ 70,653			$ 14,026				$ 3,842				$ 4,791										$ 5,332				$ 20,003				$ 15,640										$ 4,217										$ 2,802				$ 3,390	$ 3,390	$ 27,346	$ 27,346	$ 27,368	$ 2,107		$ 2,107		$ 2,076		$ 1,283		$ 1,283		$ 2,076				$ 12,139			$ 977
Amount of other-than-temporary impairment recognized in earnings	140	39	1,872	4,441			0	39	499	2,997		0		79		0		207		0		427		0		309		0		39		0		37		340		629		0		16		0		923		0		2		143		76		0		278		0		30			499	2,997	4,429	0		79	63	0		207	83	0		427	182	0	[1]	309	[1]	762	[1]	0		39	72	340		629	223	16		0	0	0	[2]	923	[2]	1,880	[2]	143		76	249	0	[2]	278	[2]	739	[2]	0		30	176	0	311				0		165				0		146		0		165	2,612	0	930	20,366	0		444	3,517
Total other-than-temporary-impairment recognized in earnings	$ 0	$ 39	$ 499	$ 3,308	$ 3,927	$ 24,795																																																										$ 0	$ 499

[1] Sold during first quarter 2011.

[2] Sold during fourth quarter 2010.

[3] Lowest rating for the security provided by any nationally recognized credit rating agency.