Fair Value Measurement (Schedule Of Carrying Value And Fair Value Of Financial Instruments Not Recorded At Fair Value) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012		Mar. 31, 2012	Dec. 31, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	$ 159,694			$ 152,265
Trading securities	3,301			2,309
Securities available for sale	2,834,076			3,168,578
Securities held to maturity	4,506			4,714
Loans held for sale	209,607			98,691
Non-covered loans and leases, net	6,104,432			5,888,098
Covered loans and leases, net	553,963			622,451
Restricted equity securities	31,712			32,581
Mortgage servicing rights	22,513		20,210	18,184	16,350	15,605	14,454
FDIC indemnification asset	68,805		78,417	91,089	116,928	131,872	146,413
Deposits	9,132,181			9,236,690
Securities sold under agreements to repurchase	149,341			124,605
Term debt	254,641			255,676
Junior subordinated debentures, at fair value	83,993			82,905
Junior subordinated debentures, at amortized cost	102,382			102,544
Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	663,776			598,766
Trading securities	3,301			2,309
Securities available for sale	2,834,076			3,168,578
Securities held to maturity	4,506			4,714
Loans held for sale	209,607			98,691
Non-covered loans and leases, net	6,020,814			5,795,130
Covered loans and leases, net	553,963			622,451
Restricted equity securities	31,712			32,581
Mortgage servicing rights	22,513			18,184
Bank owned life insurance assets	93,360			92,555
FDIC indemnification asset	68,805			91,089
Derivatives	19,928			7,955
Deposits	9,132,181			9,236,690
Securities sold under agreements to repurchase	149,341			124,605
Term debt	254,641			255,676
Junior subordinated debentures, at fair value	83,993			82,905
Junior subordinated debentures, at amortized cost	102,382			102,544
Derivatives	20,207			6,509
Estimated Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	663,776			598,766
Trading securities	3,301			2,309
Securities available for sale	2,834,076			3,168,578
Securities held to maturity	4,446			4,759
Loans held for sale	209,607			98,691
Non-covered loans and leases, net	5,978,971			5,816,714
Covered loans and leases, net	626,618			722,295
Restricted equity securities	31,712			32,581
Mortgage servicing rights	22,513			18,184
Bank owned life insurance assets	93,360			92,555
FDIC indemnification asset	24,022			47,008
Derivatives	19,928			7,955
Visa Class B common stock	23,151			19,230
Deposits	9,151,402			9,260,327
Securities sold under agreements to repurchase	149,341			124,605
Term debt	283,244			284,911
Junior subordinated debentures, at fair value	83,993	[1]		82,905
Junior subordinated debentures, at amortized cost	69,089			68,698
Derivatives	$ 20,207			$ 6,509

[1] Includes purchase accounting adjustments, net of accumulated amortization, for junior subordinated debentures assumed in connection with previous mergers as well as fair value adjustments related to trusts recorded at fair value.