Loans And Allowance For Credit Losses (Summary Of Changes In The Allowance For Credit Losses) (Details) (USD $)	3 Months Ended				9 Months Ended
	Sep. 30, 2013		Sep. 30, 2012		Sep. 30, 2013		Sep. 30, 2012		Jun. 30, 2013		Dec. 31, 2012		Jun. 30, 2012		Dec. 31, 2011
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan and Lease Losses, Provision for Loss, Gross	$ (5,573,000)		$ (1,889,000)		$ (56,598,000)		$ 24,628,000
Change In Allowance Covered By F D I C Indemnification	(2,118,000)		(5,908,000)		(9,756,000)		(12,821,000)
Allowance for Loan and Lease Losses, Write-offs	(22,826,000)		58,781,000		93,392,000		212,480,000
Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	813,912,000		973,443,000		896,087,000		1,051,685,000
Net loan and lease charge-offs	(8,698,000)		(38,578,000)		(32,210,000)		(136,424,000)
Balance at end of period	84,147,000		105,850,000		84,147,000		105,850,000		104,082,000		106,809,000		103,586,000		102,422,000
Allowance for loan losses	797,523,000		927,068,000		797,523,000		927,068,000
Reserve for unfunded lending commitments	84,147,000		105,850,000		84,147,000		105,850,000		104,082,000		106,809,000		103,586,000		102,422,000
Total allowance for credit losses	881,670,000		1,032,918,000		881,670,000		1,032,918,000
Allowance for Loan and Lease Losses, Recoveries of Bad Debts	14,128,000		(20,203,000)		(61,182,000)		(76,056,000)
Provision for Unfunded Lending Commitments	(19,935,000)		2,264,000		(22,662,000)		3,428,000
Balance at end of period	797,523,000		927,068,000		797,523,000		927,068,000
Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan and Lease Losses, Provision for Loss, Gross	(1,768,000)		(4,324,000)		(10,179,000)		20,859,000
Change In Allowance Covered By F D I C Indemnification	0		0		0		0
Allowance for Loan and Lease Losses, Write-offs	(11,465,000)		26,424,000		48,073,000		91,477,000
Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	486,353,000		542,170,000		510,908,000		561,351,000
Net loan and lease charge-offs	(5,310,000)		(14,411,000)		(21,454,000)		(58,775,000)
Balance at end of period	47,139,000		71,095,000		47,139,000		71,095,000		63,272,000		67,374,000		70,553,000		77,232,000
Allowance for loan losses	479,275,000		523,435,000		479,275,000		523,435,000
Reserve for unfunded lending commitments	47,139,000		71,095,000		47,139,000		71,095,000		63,272,000		67,374,000		70,553,000		77,232,000
Total allowance for credit losses	526,414,000		594,530,000		526,414,000		594,530,000
Allowance for Loan and Lease Losses, Recoveries of Bad Debts	6,155,000		(12,013,000)		(26,619,000)		(32,702,000)
Provision for Unfunded Lending Commitments	(16,133,000)		542,000		(20,235,000)		(6,137,000)
Balance at end of period	479,275,000		523,435,000		479,275,000		523,435,000
Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan and Lease Losses, Provision for Loss, Gross	(4,520,000)		2,157,000		(34,370,000)		(2,769,000)
Change In Allowance Covered By F D I C Indemnification	0		0		0		0
Allowance for Loan and Lease Losses, Write-offs	(5,738,000)		20,264,000		19,069,000		70,098,000
Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	251,278,000		307,965,000		276,976,000		343,747,000
Net loan and lease charge-offs	(2,750,000)		(16,952,000)		1,402,000		(47,808,000)
Balance at end of period	33,444,000		33,404,000		33,444,000		33,404,000		39,454,000		37,852,000		31,663,000		23,572,000
Allowance for loan losses	244,008,000		293,170,000		244,008,000		293,170,000
Reserve for unfunded lending commitments	33,444,000		33,404,000		33,444,000		33,404,000		39,454,000		37,852,000		31,663,000		23,572,000
Total allowance for credit losses	277,452,000		326,574,000		277,452,000		326,574,000
Allowance for Loan and Lease Losses, Recoveries of Bad Debts	2,988,000		(3,312,000)		(20,471,000)		(22,290,000)
Provision for Unfunded Lending Commitments	(6,010,000)		1,741,000		(4,408,000)		9,832,000
Balance at end of period	244,008,000		293,170,000		244,008,000		293,170,000
Consumer Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan and Lease Losses, Provision for Loss, Gross	569,000		3,351,000		(12,725,000)		9,989,000
Change In Allowance Covered By F D I C Indemnification	0		0		0		0
Allowance for Loan and Lease Losses, Write-offs	(5,535,000)		11,391,000		24,574,000		45,722,000
Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	70,366,000		102,391,000		95,656,000		123,115,000
Net loan and lease charge-offs	(2,426,000)		(8,129,000)		(14,422,000)		(35,491,000)
Balance at end of period	3,564,000		1,351,000		3,564,000		1,351,000		1,356,000		1,583,000		1,370,000		1,618,000
Allowance for loan losses	68,509,000		97,613,000		68,509,000		97,613,000
Reserve for unfunded lending commitments	3,564,000		1,351,000		3,564,000		1,351,000		1,356,000		1,583,000		1,370,000		1,618,000
Total allowance for credit losses	72,073,000		98,964,000		72,073,000		98,964,000
Allowance for Loan and Lease Losses, Recoveries of Bad Debts	3,109,000		(3,262,000)		(10,152,000)		(10,231,000)
Provision for Unfunded Lending Commitments	2,208,000		(19,000)		1,981,000		(267,000)
Balance at end of period	68,509,000		97,613,000		68,509,000		97,613,000
Federal Deposit Insurance Corporation Supported [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan and Lease Losses, Provision for Loss, Gross	146,000	[1]	(3,073,000)	[1]	676,000	[1]	(3,451,000)	[1]
Change In Allowance Covered By F D I C Indemnification	(2,118,000)	[1]	(5,908,000)	[1]	(9,756,000)	[1]	(12,821,000)	[1]
Allowance for Loan and Lease Losses, Write-offs	(88,000)	[1]	702,000	[1]	1,676,000	[1]	5,183,000	[1]
Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	5,915,000	[1]	20,917,000	[1]	12,547,000	[1]	23,472,000	[1]
Net loan and lease charge-offs	1,788,000	[1]	914,000	[1]	2,264,000	[1]	5,650,000	[1]
Balance at end of period	0	[1]	0	[1]	0	[1]	0	[1]	0	[1]	0	[1]	0	[1]	0	[1]
Allowance for loan losses	5,731,000	[1]	12,850,000	[1]	5,731,000	[1]	12,850,000	[1]
Reserve for unfunded lending commitments	0	[1]	0	[1]	0	[1]	0	[1]	0	[1]	0	[1]	0	[1]	0	[1]
Total allowance for credit losses	5,731,000	[1]	12,850,000	[1]	5,731,000	[1]	12,850,000	[1]
Allowance for Loan and Lease Losses, Recoveries of Bad Debts	1,876,000	[1]	(1,616,000)	[1]	(3,940,000)	[1]	(10,833,000)	[1]
Provision for Unfunded Lending Commitments	0	[1]	0	[1]	0	[1]		[1]
Balance at end of period	$ 5,731,000	[1]	$ 12,850,000	[1]	$ 5,731,000	[1]	$ 12,850,000	[1]

[1] The Purchased Loans section following contains further discussion related to FDIC-supported loans.