Fair Value Accounting (Financial Instruments Measured At Fair Value On A Recurring Basis) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	$ 3,991,632
Private equity investments	11,028	$ 15,771
Derivative asset positions	19,332	11,722
Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	1,128	522
Total investment securities available for sale	122,077	85,836
Private equity investments	0	0
Mutual funds held in rabbi trusts	12,844	14,140
GGL/SBA loans servicing asset	0	0
Derivative asset positions	0	0
Earnout liability	0	0
Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	2,002	3,298
Total investment securities available for sale	3,867,770	3,899,298
Private equity investments	0	0
Mutual funds held in rabbi trusts	0	0
GGL/SBA loans servicing asset	0	0
Derivative asset positions	19,332	11,722
Earnout liability	0	0
Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0	0
Total investment securities available for sale	1,785	1,935
Private equity investments	11,028	15,771
Mutual funds held in rabbi trusts	0	0
GGL/SBA loans servicing asset	3,729	4,101
Derivative asset positions	0	0
Earnout liability	14,353	11,348
U.S. Treasury securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	122,077
U.S. Government agency securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	38,382
Mortgage-backed securities issued by U.S. Government agencies
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	97,205
Mortgage-backed securities issued by U.S. Government sponsored enterprises
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	2,398,650
Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	1,188,518
Commercial mortgage-backed securities issued by U.S. Government sponsored enterprises
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	129,865
State and municipal securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	16,935
Fair Value, Measurements, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	3,130	3,820
Mortgage loans held for sale	37,129	48,024
Total investment securities available for sale	3,991,632	3,987,069
Private equity investments	11,028	15,771
Mutual funds held in rabbi trusts	12,844	14,140
GGL/SBA loans servicing asset	3,729	4,101
Derivative asset positions	19,332	11,722
Trading account liabilities		1,000
Earnout liability	14,353	11,348
Derivative liabilities	18,208	17,097
Fair Value, Measurements, Recurring | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	1,128	522
Mortgage loans held for sale	0	0
Total investment securities available for sale	122,077	85,836
Private equity investments	0	0
Mutual funds held in rabbi trusts	12,844	14,140
GGL/SBA loans servicing asset	0	0
Derivative asset positions	0	0
Trading account liabilities		0
Earnout liability	0	0
Derivative liabilities	0	0
Fair Value, Measurements, Recurring | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	2,002	3,298
Mortgage loans held for sale	37,129	48,024
Total investment securities available for sale	3,867,770	3,899,298
Private equity investments	0	0
Mutual funds held in rabbi trusts	0	0
GGL/SBA loans servicing asset	0	0
Derivative asset positions	19,332	11,722
Trading account liabilities		1,000
Earnout liability	0	0
Derivative liabilities	16,535	12,767
Fair Value, Measurements, Recurring | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0	0
Mortgage loans held for sale	0	0
Total investment securities available for sale	1,785	1,935
Private equity investments	11,028	15,771
Mutual funds held in rabbi trusts	0	0
GGL/SBA loans servicing asset	3,729	4,101
Derivative asset positions	0	0
Trading account liabilities		0
Earnout liability	14,353	11,348
Derivative liabilities	1,673	4,330
Fair Value, Measurements, Recurring | U.S. Treasury securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	122,077	82,674
Fair Value, Measurements, Recurring | U.S. Treasury securities | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	122,077	82,674
Fair Value, Measurements, Recurring | U.S. Treasury securities | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	0	0
Fair Value, Measurements, Recurring | U.S. Treasury securities | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	0	0
Fair Value, Measurements, Recurring | U.S. Government agency securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	38,382	10,862
Fair Value, Measurements, Recurring | U.S. Government agency securities | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	0	0
Fair Value, Measurements, Recurring | U.S. Government agency securities | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	38,382	10,862
Fair Value, Measurements, Recurring | U.S. Government agency securities | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	0	0
Fair Value, Measurements, Recurring | Mortgage-backed securities issued by U.S. Government agencies
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	97,205	120,440
Fair Value, Measurements, Recurring | Mortgage-backed securities issued by U.S. Government agencies | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	0	0
Fair Value, Measurements, Recurring | Mortgage-backed securities issued by U.S. Government agencies | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	97,205	120,440
Fair Value, Measurements, Recurring | Mortgage-backed securities issued by U.S. Government agencies | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	0	0
Fair Value, Measurements, Recurring | Mortgage-backed securities issued by U.S. Government sponsored enterprises
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	2,398,650	2,595,626
Fair Value, Measurements, Recurring | Mortgage-backed securities issued by U.S. Government sponsored enterprises | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	0	0
Fair Value, Measurements, Recurring | Mortgage-backed securities issued by U.S. Government sponsored enterprises | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	2,398,650	2,595,626
Fair Value, Measurements, Recurring | Mortgage-backed securities issued by U.S. Government sponsored enterprises | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	0	0
Fair Value, Measurements, Recurring | Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	1,188,518	1,111,999
Fair Value, Measurements, Recurring | Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	0	0
Fair Value, Measurements, Recurring | Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	1,188,518	1,111,999
Fair Value, Measurements, Recurring | Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	0	0
Fair Value, Measurements, Recurring | Commercial mortgage-backed securities issued by U.S. Government sponsored enterprises
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	129,865	44,897
Fair Value, Measurements, Recurring | Commercial mortgage-backed securities issued by U.S. Government sponsored enterprises | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	0	0
Fair Value, Measurements, Recurring | Commercial mortgage-backed securities issued by U.S. Government sponsored enterprises | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	129,865	44,897
Fair Value, Measurements, Recurring | Commercial mortgage-backed securities issued by U.S. Government sponsored enterprises | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	0	0
Fair Value, Measurements, Recurring | State and municipal securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale		180
Fair Value, Measurements, Recurring | State and municipal securities | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale		0
Fair Value, Measurements, Recurring | State and municipal securities | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale		180
Fair Value, Measurements, Recurring | State and municipal securities | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale		0
Fair Value, Measurements, Recurring | Corporate debt and other debt securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	16,935	20,391
Fair Value, Measurements, Recurring | Corporate debt and other debt securities | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	0	3,162
Fair Value, Measurements, Recurring | Corporate debt and other debt securities | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	15,150	15,294
Fair Value, Measurements, Recurring | Corporate debt and other debt securities | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investment securities available for sale	1,785	1,935
Fair Value, Measurements, Recurring | Mutual funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity Securities, FV-NI	3,168
Fair Value, Measurements, Recurring | Mutual funds | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity Securities, FV-NI	3,168
Fair Value, Measurements, Recurring | Mutual funds | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity Securities, FV-NI	0
Fair Value, Measurements, Recurring | Mutual funds | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity Securities, FV-NI	0
Fair Value, Measurements, Recurring | Interest rate contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative asset positions	18,388	10,786
Derivative liabilities	15,716	12,638
Fair Value, Measurements, Recurring | Interest rate contracts | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative asset positions	0	0
Derivative liabilities	0	0
Fair Value, Measurements, Recurring | Interest rate contracts | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative asset positions	18,388	10,786
Derivative liabilities	15,716	12,638
Fair Value, Measurements, Recurring | Interest rate contracts | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative asset positions	0	0
Derivative liabilities	0	0
Fair Value, Measurements, Recurring | Mortgage derivatives
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative asset positions	944	936
Derivative liabilities	819	129
Fair Value, Measurements, Recurring | Mortgage derivatives | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative asset positions	0	0
Derivative liabilities	0	0
Fair Value, Measurements, Recurring | Mortgage derivatives | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative asset positions	944	936
Derivative liabilities	819	129
Fair Value, Measurements, Recurring | Mortgage derivatives | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative asset positions	0	0
Derivative liabilities	0	0
Fair Value, Measurements, Recurring | Visa derivative
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	1,673	4,330
Fair Value, Measurements, Recurring | Visa derivative | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	0	0
Fair Value, Measurements, Recurring | Visa derivative | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	0	0
Fair Value, Measurements, Recurring | Visa derivative | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	1,673	4,330
Fair Value, Measurements, Recurring | U.S. Government agency securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	44	3,002
Fair Value, Measurements, Recurring | U.S. Government agency securities | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0	0
Fair Value, Measurements, Recurring | U.S. Government agency securities | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	44	3,002
Fair Value, Measurements, Recurring | U.S. Government agency securities | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0	0
Fair Value, Measurements, Recurring | State and municipal securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	1,064
Fair Value, Measurements, Recurring | State and municipal securities | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0
Fair Value, Measurements, Recurring | State and municipal securities | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	1,064
Fair Value, Measurements, Recurring | State and municipal securities | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0
Fair Value, Measurements, Recurring | Collateralized mortgage obligations issued by U.S. Government sponsored agencies or enterprises
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities		296
Fair Value, Measurements, Recurring | Collateralized mortgage obligations issued by U.S. Government sponsored agencies or enterprises | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities		0
Fair Value, Measurements, Recurring | Collateralized mortgage obligations issued by U.S. Government sponsored agencies or enterprises | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities		296
Fair Value, Measurements, Recurring | Collateralized mortgage obligations issued by U.S. Government sponsored agencies or enterprises | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities		0
Fair Value, Measurements, Recurring | Other investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	2,022	522
Fair Value, Measurements, Recurring | Other investments | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	1,128	522
Fair Value, Measurements, Recurring | Other investments | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	894	0
Fair Value, Measurements, Recurring | Other investments | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	$ 0	$ 0