Investment Securities (Securities With Other-Than-Temporary Impairment) (Details) (USD $) In Thousands	3 Months Ended			6 Months Ended			12 Months Ended
	Jun. 30, 2011		Jun. 30, 2010	Jun. 30, 2011		Jun. 30, 2010	Dec. 31, 2010		Dec. 31, 2009
Amortized Cost	$ 2,168,082			$ 2,168,082			$ 1,953,842
Amount of other-than-temporary impairment recognized in earnings	1,433		2,764	1,732		4,402
Total other-than-temporary-impairment recognized in earnings	200		2,764	499		3,269	3,927		24,795
Mortgage-Backed Securities - Non-Agency Group 1 [Member]
Amortized Cost	40,955		120,823	40,955		120,823	134,168
Amount of other-than-temporary impairment recognized in earnings	200		2,453	499		2,958
Total other-than-temporary-impairment recognized in earnings	200			499
Mortgage-Backed Securities - Non-Agency Group 1 [Member] | BAFC Ser 4 [Member]
Vintage						2007
Lowest Credit Rating			CCC			CCC
Amortized Cost			14,026			14,026
Amount of other-than-temporary impairment recognized in earnings			79			79
Mortgage-Backed Securities - Non-Agency Group 1 [Member] | CWALT Ser 73CB 1 [Member]
Vintage						2005
Lowest Credit Rating			CCC			CCC
Amortized Cost			6,606			6,606
Amount of other-than-temporary impairment recognized in earnings			150			207
Mortgage-Backed Securities - Non-Agency Group 1 [Member] | CWALT Ser 73CB 2 [Member]
Vintage						2005
Lowest Credit Rating			CCC			CCC
Amortized Cost			8,353			8,353
Amount of other-than-temporary impairment recognized in earnings			324			427
Mortgage-Backed Securities - Non-Agency Group 1 [Member] | CWHL 2006-10 [Member]
Vintage						2006
Lowest Credit Rating			CC			CC
Amortized Cost			10,030			10,030
Amount of other-than-temporary impairment recognized in earnings			105			309
Mortgage-Backed Securities - Non-Agency Group 1 [Member] | CWHL 2005-20 [Member]
Vintage						2005
Lowest Credit Rating			B-			B-
Amortized Cost			10,987			10,987
Amount of other-than-temporary impairment recognized in earnings			7			39
Mortgage-Backed Securities - Non-Agency Group 1 [Member] | FHASI Ser 4 [Member]
Vintage				2007		2007
Lowest Credit Rating	CC	[1]	CCC	CC	[1]	CCC
Amortized Cost	21,098		21,654	21,098		21,654
Amount of other-than-temporary impairment recognized in earnings	138		592	340		592
Mortgage-Backed Securities - Non-Agency Group 1 [Member] | HALO Ser 1R [Member]
Vintage				2006
Lowest Credit Rating	B	[1]		B	[1]
Amortized Cost	15,640			15,640
Amount of other-than-temporary impairment recognized in earnings	16			16
Mortgage-Backed Securities - Non-Agency Group 1 [Member] | RFMSI Ser S9 [Member]
Vintage						2006
Lowest Credit Rating			CC			CC
Amortized Cost			32,070			32,070
Amount of other-than-temporary impairment recognized in earnings			923			923
Mortgage-Backed Securities - Non-Agency Group 1 [Member] | RFMSI Ser S10 [Member]
Vintage				2006		2006
Lowest Credit Rating	CC	[1]	CCC	CC	[1]	CCC
Amortized Cost	4,217		4,362	4,217		4,362
Amount of other-than-temporary impairment recognized in earnings	46		74	143		74
Mortgage-Backed Securities - Non-Agency Group 1 [Member] | RALI QS2 [Member]
Vintage						2006
Lowest Credit Rating			CC			CC
Amortized Cost			6,968			6,968
Amount of other-than-temporary impairment recognized in earnings			199			278
Mortgage-Backed Securities - Non-Agency Group 1 [Member] | RFMSI S1 [Member]
Vintage						2006
Lowest Credit Rating			CCC			CCC
Amortized Cost			5,767			5,767
Amount of other-than-temporary impairment recognized in earnings			0			30
Mortgage-Backed Securities - Non-Agency Group 2 [Member]
Amortized Cost	74,524			74,524
Amount of other-than-temporary impairment recognized in earnings				499			2,997		4,429
Mortgage-Backed Securities - Non-Agency Group 2 [Member] | BAFC Ser 4 [Member]
Vintage				2007
Lowest Credit Rating	CCC	[1]		CCC	[1]
Amortized Cost	14,026			14,026
Amount of other-than-temporary impairment recognized in earnings				0			79		63
Mortgage-Backed Securities - Non-Agency Group 2 [Member] | CWALT Ser 73CB 1 [Member]
Vintage				2005
Lowest Credit Rating	CCC	[1]		CCC	[1]
Amortized Cost	4,428			4,428
Amount of other-than-temporary impairment recognized in earnings				0			207		83
Mortgage-Backed Securities - Non-Agency Group 2 [Member] | CWALT Ser 73CB 2 [Member]
Vintage				2005
Lowest Credit Rating	CCC	[1]		CCC	[1]
Amortized Cost	5,388			5,388
Amount of other-than-temporary impairment recognized in earnings				0			427		182
Mortgage-Backed Securities - Non-Agency Group 2 [Member] | CWHL 2006-10 [Member]
Vintage				2006	[2]
Amount of other-than-temporary impairment recognized in earnings				0	[2]		309	[2]	762	[2]
Mortgage-Backed Securities - Non-Agency Group 2 [Member] | CWHL 2005-20 [Member]
Vintage				2005
Lowest Credit Rating	B-	[1]		B-	[1]
Amortized Cost	6,376			6,376
Amount of other-than-temporary impairment recognized in earnings				0			39		72
Mortgage-Backed Securities - Non-Agency Group 2 [Member] | FHASI Ser 4 [Member]
Vintage				2007
Lowest Credit Rating	CC	[1]		CC	[1]
Amortized Cost	21,098			21,098
Amount of other-than-temporary impairment recognized in earnings				340			629		223
Mortgage-Backed Securities - Non-Agency Group 2 [Member] | HALO Ser 1R [Member]
Vintage				2006
Lowest Credit Rating	B	[1]		B	[1]
Amortized Cost	15,640			15,640
Amount of other-than-temporary impairment recognized in earnings				16			0		0
Mortgage-Backed Securities - Non-Agency Group 2 [Member] | RFMSI Ser S9 [Member]
Vintage				2006	[3]
Amount of other-than-temporary impairment recognized in earnings				0	[3]		923	[3]	1,880	[3]
Mortgage-Backed Securities - Non-Agency Group 2 [Member] | RFMSI Ser S10 [Member]
Vintage				2006
Lowest Credit Rating	CC	[1]		CC	[1]
Amortized Cost	4,217			4,217
Amount of other-than-temporary impairment recognized in earnings				143			76		249
Mortgage-Backed Securities - Non-Agency Group 2 [Member] | RALI QS2 [Member]
Vintage				2006	[3]
Amount of other-than-temporary impairment recognized in earnings				0	[3]		278	[3]	739	[3]
Mortgage-Backed Securities - Non-Agency Group 2 [Member] | RFMSI S1 [Member]
Vintage				2006
Lowest Credit Rating	CCC	[1]		CCC	[1]
Amortized Cost	3,351			3,351
Amount of other-than-temporary impairment recognized in earnings				0			30		176
Pooled Trust Preferred Securities Group 1 [Member]
Amortized Cost	27,349		3,403	27,349		3,403	27,368
Amount of other-than-temporary impairment recognized in earnings			311			311
Pooled Trust Preferred Securities Group 1 [Member] | MM Community Funding IX [Member]
Vintage						2003
Lowest Credit Rating	C	[1]	C	C	[1]	C
Amortized Cost	2,081		1,287	2,081		1,287
Amount of other-than-temporary impairment recognized in earnings			146			146
Pooled Trust Preferred Securities Group 1 [Member] | TROPC [Member]
Vintage						2003
Lowest Credit Rating			C			C
Amortized Cost			2,116			2,116
Amount of other-than-temporary impairment recognized in earnings			165			165
MM Community Funding IX [Member] | Pooled Trust Preferred Securities Group 2 [Member]
Vintage				2003
Lowest Credit Rating	C	[1]		C	[1]
Amortized Cost	2,081			2,081
Amount of other-than-temporary impairment recognized in earnings				0			165		2,612
Pooled Trust Preferred Securities Group 2 [Member]
Amortized Cost	12,159			12,159
Amount of other-than-temporary impairment recognized in earnings				0			930		20,366
Pooled Trust Preferred Securities Group 2 [Member] | TROPC [Member]
Vintage				2003
Lowest Credit Rating	C	[1]		C	[1]
Amortized Cost	978			978
Amount of other-than-temporary impairment recognized in earnings				$ 0			$ 444		$ 3,517

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

[2] Sold during first quarter 2011.

[3] Sold during fourth quarter 2010.