Loans (Details Textual) (USD $)	3 Months Ended				9 Months Ended						3 Months Ended				9 Months Ended
	Sep. 30, 2012		Sep. 30, 2011		Sep. 30, 2012		Sep. 30, 2011		Dec. 31, 2011		Sep. 30, 2012 Covered Loans [Member]		Sep. 30, 2011 Covered Loans [Member]		Sep. 30, 2012 Covered Loans [Member]		Sep. 30, 2011 Covered Loans [Member]		Dec. 31, 2011 Covered Loans [Member]		Sep. 30, 2012 Acquired Loans Noncovered [Member]	Dec. 31, 2011 Acquired Loans Noncovered [Member]	Sep. 30, 2011 Acquired Loans Noncovered [Member]	Sep. 30, 2012 Loss Share Receivable [Member]	Jun. 30, 2012 Loss Share Receivable [Member]	Dec. 31, 2011 Loss Share Receivable [Member]	Sep. 30, 2011 Loss Share Receivable [Member]	Jun. 30, 2011 Loss Share Receivable [Member]	Dec. 31, 2010 Loss Share Receivable [Member]	Sep. 30, 2012 Legacy Loans [Member]	Dec. 31, 2011 Legacy Loans [Member]	Sep. 30, 2011 Legacy Loans [Member]	Sep. 30, 2012 Consumer Loan [Member]	Sep. 30, 2012 Commercial Real Estate Other Receivable [Member] Covered Loans [Member]		Dec. 31, 2011 Commercial Real Estate Other Receivable [Member] Covered Loans [Member]		Sep. 30, 2011 Commercial Real Estate Other Receivable [Member] Covered Loans [Member]		Sep. 30, 2012 Commercial Real Estate Other Receivable [Member] Acquired Loans Noncovered [Member]	Dec. 31, 2011 Commercial Real Estate Other Receivable [Member] Acquired Loans Noncovered [Member]	Sep. 30, 2011 Commercial Real Estate Other Receivable [Member] Acquired Loans Noncovered [Member]	Sep. 30, 2012 Commercial Real Estate Other Receivable [Member] Legacy Loans [Member]	Dec. 31, 2011 Commercial Real Estate Other Receivable [Member] Legacy Loans [Member]	Sep. 30, 2011 Commercial Real Estate Other Receivable [Member] Legacy Loans [Member]	Sep. 30, 2012 Commercial Construction Financing Receivable [Member] Covered Loans [Member]		Dec. 31, 2011 Commercial Construction Financing Receivable [Member] Covered Loans [Member]		Sep. 30, 2011 Commercial Construction Financing Receivable [Member] Covered Loans [Member]		Sep. 30, 2012 Commercial Construction Financing Receivable [Member] Legacy Loans [Member]	Dec. 31, 2011 Commercial Construction Financing Receivable [Member] Legacy Loans [Member]	Sep. 30, 2011 Commercial Construction Financing Receivable [Member] Legacy Loans [Member]	Sep. 30, 2012 Commercial Leases Financing Receivable [Member] Covered Loans [Member]	Dec. 31, 2011 Commercial Leases Financing Receivable [Member] Covered Loans [Member]	Sep. 30, 2011 Commercial Leases Financing Receivable [Member] Covered Loans [Member]	Sep. 30, 2012 Commercial Leases Financing Receivable [Member] Acquired Loans Noncovered [Member]	Dec. 31, 2011 Commercial Leases Financing Receivable [Member] Acquired Loans Noncovered [Member]	Sep. 30, 2011 Commercial Leases Financing Receivable [Member] Acquired Loans Noncovered [Member]	Sep. 30, 2012 Commercial Leases Financing Receivable [Member] Legacy Loans [Member]	Dec. 31, 2011 Commercial Leases Financing Receivable [Member] Legacy Loans [Member]	Sep. 30, 2011 Commercial Leases Financing Receivable [Member] Legacy Loans [Member]	Sep. 30, 2012 Consumer Installment Financing Receivable [Member] Covered Loans [Member]		Dec. 31, 2011 Consumer Installment Financing Receivable [Member] Covered Loans [Member]		Sep. 30, 2011 Consumer Installment Financing Receivable [Member] Covered Loans [Member]		Sep. 30, 2012 Consumer Installment Financing Receivable [Member] Acquired Loans Noncovered [Member]	Dec. 31, 2011 Consumer Installment Financing Receivable [Member] Acquired Loans Noncovered [Member]	Sep. 30, 2011 Consumer Installment Financing Receivable [Member] Acquired Loans Noncovered [Member]	Sep. 30, 2012 Consumer Installment Financing Receivable [Member] Legacy Loans [Member]	Dec. 31, 2011 Consumer Installment Financing Receivable [Member] Legacy Loans [Member]	Sep. 30, 2011 Consumer Installment Financing Receivable [Member] Legacy Loans [Member]	Sep. 30, 2012 Consumer Home Equity Lines Financing Receivable [Member] Covered Loans [Member]		Dec. 31, 2011 Consumer Home Equity Lines Financing Receivable [Member] Covered Loans [Member]		Sep. 30, 2011 Consumer Home Equity Lines Financing Receivable [Member] Covered Loans [Member]		Sep. 30, 2012 Consumer Home Equity Lines Financing Receivable [Member] Acquired Loans Noncovered [Member]	Dec. 31, 2011 Consumer Home Equity Lines Financing Receivable [Member] Acquired Loans Noncovered [Member]	Sep. 30, 2011 Consumer Home Equity Lines Financing Receivable [Member] Acquired Loans Noncovered [Member]	Sep. 30, 2012 Consumer Home Equity Lines Financing Receivable [Member] Legacy Loans [Member]	Dec. 31, 2011 Consumer Home Equity Lines Financing Receivable [Member] Legacy Loans [Member]	Sep. 30, 2011 Consumer Home Equity Lines Financing Receivable [Member] Legacy Loans [Member]	Sep. 30, 2012 Consumer Credit Card Financing Receivable [Member] Legacy Loans [Member]	Dec. 31, 2011 Consumer Credit Card Financing Receivable [Member] Legacy Loans [Member]	Sep. 30, 2011 Consumer Credit Card Financing Receivable [Member] Legacy Loans [Member]	Sep. 30, 2012 Consumer Residential Mortgages Financing Receivable [Member] Covered Loans [Member]		Dec. 31, 2011 Consumer Residential Mortgages Financing Receivable [Member] Covered Loans [Member]		Sep. 30, 2011 Consumer Residential Mortgages Financing Receivable [Member] Covered Loans [Member]		Sep. 30, 2012 Consumer Residential Mortgages Financing Receivable [Member] Acquired Loans Noncovered [Member]	Dec. 31, 2011 Consumer Residential Mortgages Financing Receivable [Member] Acquired Loans Noncovered [Member]	Sep. 30, 2011 Consumer Residential Mortgages Financing Receivable [Member] Acquired Loans Noncovered [Member]	Sep. 30, 2012 Consumer Residential Mortgages Financing Receivable [Member] Legacy Loans [Member]	Dec. 31, 2011 Consumer Residential Mortgages Financing Receivable [Member] Legacy Loans [Member]	Sep. 30, 2011 Consumer Residential Mortgages Financing Receivable [Member] Legacy Loans [Member]	Sep. 30, 2012 Commercial and Industrial Financing Receivable [Member] Covered Loans [Member]		Dec. 31, 2011 Commercial and Industrial Financing Receivable [Member] Covered Loans [Member]		Sep. 30, 2011 Commercial and Industrial Financing Receivable [Member] Covered Loans [Member]		Sep. 30, 2012 Commercial and Industrial Financing Receivable [Member] Acquired Loans Noncovered [Member]	Dec. 31, 2011 Commercial and Industrial Financing Receivable [Member] Acquired Loans Noncovered [Member]	Sep. 30, 2011 Commercial and Industrial Financing Receivable [Member] Acquired Loans Noncovered [Member]	Sep. 30, 2012 Commercial and Industrial Financing Receivable [Member] Legacy Loans [Member]	Dec. 31, 2011 Commercial and Industrial Financing Receivable [Member] Legacy Loans [Member]	Sep. 30, 2011 Commercial and Industrial Financing Receivable [Member] Legacy Loans [Member]	May 14, 2010 Midwest Transaction [Member]	Feb. 19, 2010 First Bank Branches [Member]	Feb. 19, 2010 George Washington [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	$ 8,316,420,000	[1]	$ 7,631,572,000	[1]	$ 8,316,420,000	[1]	$ 7,631,572,000	[1]	$ 7,748,944,000	[1]											$ 56,000,000	$ 113,200,000	$ 178,000,000
Covered Loans and Leases Receivable Gross	1,174,929,000	[2]	1,647,218,000	[2]	1,174,929,000	[2]	1,647,218,000	[2]	1,497,140,000															131,872,000	152,615,000	205,664,000	220,471,000	239,424,000	288,605,000
Unamortized Loan Commitment and Origination Fees and Unamortized Discounts or Premiums	5,800,000		5,800,000		5,800,000		5,800,000		6,000,000
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Acquired During Period, at Acquisition, at Fair Value																																																																																																																			1,800,000,000	275,600,000	177,800,000
Acquired Non Impaired Loans	162,600,000				162,600,000
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	1,333,127,000		1,742,815,000		1,333,127,000		1,742,815,000		1,609,852,000
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield, Reclassifications from Nonaccretable Difference	6,008,000		27,160,000		30,814,000		67,118,000
Provision for Loan Losses Before Benefit Attributable to FDIC Loss Share Agreements											7,698,000		12,992,000		28,177,000		48,657,000
Benefit Attributable to FDIC Loss Share Agreements											(1,484,000)		(8,224,000)		(12,601,000)		(31,077,000)
Loans Payments Past Due	90
Credit Card Loans Past Due	120
Allowance for Loan and Lease Losses, Period Increase (Decrease)											6,200,000
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due											263,019,000	[3]	309,849,000	[4]	263,019,000	[3]	309,849,000	[4]	269,976,000	[5]	2,715,000	1,743,000	3,423,000							29,819,000	60,449,000	61,700,000		184,067,000	[3]	170,795,000	[5]	198,957,000	[4]	2,565,000	1,675,000	3,284,000	14,311,000	29,976,000	33,003,000	41,325,000	[3]	57,978,000	[5]	68,016,000	[4]	853,000	7,837,000	8,943,000							0	0	0	35,000	[3]	60,000	[5]	42,000	[4]	0	1,000	0	4,834,000	5,167,000	5,052,000	1,981,000	[3]	1,088,000	[5]	979,000	[4]	100,000	1,000	1,000	1,311,000	1,241,000	922,000	808,000	1,019,000	771,000	8,576,000	[3]	14,254,000	[5]	9,364,000	[4]	0	0	0	6,233,000	9,719,000	7,648,000	27,035,000	[3]	25,801,000	[5]	32,491,000	[4]	50,000	66,000	138,000	1,469,000	5,490,000	5,361,000
Financing Receivable, Recorded Investment, Past Due											310,588,000	[3]	365,484,000	[4]	310,588,000	[3]	365,484,000	[4]	336,787,000	[5]	2,893,000	2,262,000	7,429,000							81,820,000	107,913,000	129,809,000		210,951,000	[3]	204,069,000	[5]	228,406,000	[4]	2,565,000	2,127,000	6,726,000	21,364,000	40,982,000	49,178,000	42,323,000	[3]	63,858,000	[5]	70,275,000	[4]	969,000	7,876,000	11,441,000							7,000	0	0	2,324,000	[3]	109,000	[5]	683,000	[4]	50,000	1,000	1,000	17,148,000	20,086,000	18,367,000	3,814,000	[3]	4,838,000	[5]	2,375,000	[4]	165,000	68,000	38,000	3,558,000	4,646,000	4,127,000	2,355,000	2,816,000	2,694,000	20,206,000	[3]	28,524,000	[5]	25,233,000	[4]	63,000	0	78,000	23,374,000	23,556,000	19,747,000	30,970,000	[3]	35,389,000	[5]	38,512,000	[4]	50,000	66,000	586,000	13,045,000	7,951,000	24,255,000
Financing Receivable, Recorded Investment, Current											732,470,000	[3]	1,061,263,000	[4]	732,470,000	[3]	1,061,263,000	[4]	954,689,000	[5]	53,101,000	110,906,000	170,530,000							8,178,606,000	7,527,863,000	7,323,804,000		412,323,000	[3]	573,779,000	[5]	649,812,000	[4]	29,653,000	60,616,000	101,069,000	2,099,760,000	1,951,211,000	1,907,048,000	19,453,000	[3]	26,051,000	[5]	29,779,000	[4]	308,136,000	269,459,000	241,137,000							110,931,000	73,530,000	57,992,000	6,036,000	[3]	10,013,000	[5]	10,455,000	[4]	1,888,000	2,519,000	3,283,000	1,301,995,000	1,241,059,000	1,249,676,000	119,364,000	[3]	136,710,000	[5]	143,757,000	[4]	18,007,000	19,223,000	20,718,000	768,013,000	720,045,000	718,494,000	141,563,000	143,540,000	140,016,000	43,573,000	[3]	45,986,000	[5]	48,578,000	[4]	1,187,000	1,840,000	1,778,000	414,438,000	388,268,000	375,706,000	131,721,000	[3]	162,150,000	[5]	178,882,000	[4]	2,366,000	26,708,000	43,682,000	3,033,770,000	2,740,751,000	2,633,735,000
Financing Receivable	8,316,420,000				8,316,420,000						1,043,058,000	[3]	1,426,747,000	[4]	1,043,058,000	[3]	1,426,747,000	[4]	1,291,476,000	[5]	55,994,000	113,168,000	177,959,000							8,260,426,000	7,635,776,000	7,453,613,000		623,274,000	[3]	777,848,000	[5]	878,218,000	[4]	32,218,000	62,743,000	107,795,000	2,121,124,000	1,992,193,000	1,956,226,000	61,776,000	[3]	89,909,000	[5]	100,054,000	[4]	309,105,000	277,335,000	252,578,000	0	0	0	0	0	0	110,938,000	73,530,000	57,992,000	8,360,000	[3]	10,122,000	[5]	11,138,000	[4]	1,938,000	2,520,000	3,284,000	1,319,143,000	1,261,145,000	1,268,043,000	123,178,000	[3]	141,548,000	[5]	146,132,000	[4]	18,172,000	19,291,000	20,756,000	771,571,000	724,691,000	722,621,000	143,918,000	146,356,000	142,710,000	63,779,000	[3]	74,510,000	[5]	73,811,000	[4]	1,250,000	1,840,000	1,856,000	437,812,000	411,824,000	395,453,000	162,691,000	[3]	197,539,000	[5]	217,394,000	[4]	2,416,000	26,774,000	44,268,000	3,046,815,000	2,748,702,000	2,657,990,000
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing																					132,000	3,000	395,000							9,559,000	11,373,000	4,008,000								0	0	394,000	1,862,000	984,000	0							0	609,000	0							0	0	0							0	1,000	0	4,439,000	4,864,000	1,125,000							132,000	2,000	1,000	409,000	796,000	922,000	393,000	403,000	357,000							0	0	0	2,399,000	3,252,000	1,481,000							0	0	0	57,000	465,000	123,000
Financing Receivable, Recorded Investment, Nonaccrual Status																					2,831,000	2,949,000	3,696,000							47,480,000	61,682,000	64,207,000	10,600,000							2,762,000	2,880,000	3,558,000	17,812,000	36,025,000	39,560,000							923,000	7,575,000	10,580,000							0	0	0							0	0	0	3,267,000	624,000	438,000							0	0	0	1,858,000	1,102,000	753,000	525,000	622,000	614,000							0	0	0	13,169,000	6,468,000	6,166,000							69,000	69,000	138,000	9,926,000	9,266,000	6,096,000
Covered Loans Loss Share Receivable	$ 131,872,000		$ 220,471,000		$ 131,872,000		$ 220,471,000		$ 205,664,000

[1] (a)Includes acquired, noncovered loans of $56.0 million, $113.2 million and $178.0 million as of September 30, 2012, December 31, 2011 and September 30, 2011, respectively.

[2] Includes loss share receivable of $131.9 million, $205.7 million and $220.5 million as of September 30, 2012, December 31, 2011 and September 30, 2011, respectively.

[3] Excludes loss share receivable of $131.9 million as of September 30, 2012.

[4] Excludes loss share receivable of $220.5 million as of September 30, 2011

[5] Excludes loss share receivable of $205.7 million as of December 31, 2011.