Allowance for Loan Losses Allowance for Losses on Lending-Related Commitments and Impaired Loans (Summary of Recorded Investment Based on Performance of Loans by Class) (Details) - USD ($) $ in Thousands		Dec. 31, 2015	Dec. 31, 2014
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		$ 17,118,117	$ 14,409,398
Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		17,034,060	14,330,721
Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		84,057	78,677
Commercial
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		4,713,909	3,924,394
Commercial | Commercial and industrial
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		2,851,354	2,214,480
Commercial | Franchise
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		245,228	252,200
Commercial | Mortgage warehouse lines of credit
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		222,806	139,003
Commercial | Community Advanatage - homeowners association
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		130,986	106,364
Commercial | Aircraft
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		5,327	8,065
Commercial | Asset-based lending
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		742,684	806,402
Commercial | Tax exempt
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		267,273	217,487
Commercial | Leases
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		226,074	160,136
Commercial | Other
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		3,588	11,034
Commercial | PCI - commercial
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans	[1],[2]	18,589	9,223
Commercial | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		4,700,656	3,914,763
Commercial | Performing | Commercial and industrial
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		2,838,932	2,204,874
Commercial | Performing | Franchise
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		245,228	252,200
Commercial | Performing | Mortgage warehouse lines of credit
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		222,806	139,003
Commercial | Performing | Community Advanatage - homeowners association
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		130,986	106,364
Commercial | Performing | Aircraft
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		5,039	8,065
Commercial | Performing | Asset-based lending
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		742,676	806,377
Commercial | Performing | Tax exempt
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		267,273	217,487
Commercial | Performing | Leases
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		225,539	160,136
Commercial | Performing | Other
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		3,588	11,034
Commercial | Performing | PCI - commercial
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans	[2]	18,589	9,223
Commercial | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		13,253	9,631
Commercial | Non-performing | Commercial and industrial
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		12,422	9,606
Commercial | Non-performing | Franchise
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		0	0
Commercial | Non-performing | Mortgage warehouse lines of credit
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		0	0
Commercial | Non-performing | Community Advanatage - homeowners association
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		0	0
Commercial | Non-performing | Aircraft
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		288	0
Commercial | Non-performing | Asset-based lending
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		8	25
Commercial | Non-performing | Tax exempt
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		0	0
Commercial | Non-performing | Leases
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		535	0
Commercial | Non-performing | Other
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		0	0
Commercial | Non-performing | PCI - commercial
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans	[2]	0	0
Commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		5,529,289	4,505,753
Commercial real estate | Residential construction
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		70,381	38,696
Commercial real estate | Commercial construction
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		288,279	187,766
Commercial real estate | Land
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		78,417	91,830
Commercial real estate | Office
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		863,001	705,432
Commercial real estate | Industrial
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		727,648	623,970
Commercial real estate | Retail
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		868,399	731,488
Commercial real estate | Multi-family
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		742,349	605,742
Commercial real estate | Mixed use and other
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		1,732,816	1,465,117
Commercial real estate | PCI - commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans	[1],[2]	157,999	55,712
Commercial real estate | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		5,502,644	4,479,148
Commercial real estate | Performing | Residential construction
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		70,108	38,696
Commercial real estate | Performing | Commercial construction
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		288,246	187,536
Commercial real estate | Performing | Land
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		76,666	89,174
Commercial real estate | Performing | Office
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		858,382	698,144
Commercial real estate | Performing | Industrial
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		718,084	621,578
Commercial real estate | Performing | Retail
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		866,639	727,336
Commercial real estate | Performing | Multi-family
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		740,395	605,493
Commercial real estate | Performing | Mixed use and other
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		1,726,125	1,455,479
Commercial real estate | Performing | PCI - commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans	[2]	157,999	55,712
Commercial real estate | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		26,645	26,605
Commercial real estate | Non-performing | Residential construction
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		273	0
Commercial real estate | Non-performing | Commercial construction
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		33	230
Commercial real estate | Non-performing | Land
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		1,751	2,656
Commercial real estate | Non-performing | Office
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		4,619	7,288
Commercial real estate | Non-performing | Industrial
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		9,564	2,392
Commercial real estate | Non-performing | Retail
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		1,760	4,152
Commercial real estate | Non-performing | Multi-family
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		1,954	249
Commercial real estate | Non-performing | Mixed use and other
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		6,691	9,638
Commercial real estate | Non-performing | PCI - commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans	[2]	0	0
Home equity
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		784,675	716,293
Home equity | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		777,827	710,119
Home equity | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		6,848	6,174
Residential real estate
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		607,451	483,542
Residential real estate | Residential real estate
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		603,985	481,308
Residential real estate | PCI - residential real estate
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans	[1],[2]	3,466	2,234
Residential real estate | Performing | Residential real estate
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		591,942	465,806
Residential real estate | Performing | PCI - residential real estate
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans	[2]	3,466	2,234
Residential real estate | Non-performing | Residential real estate
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		12,043	15,502
Residential real estate | Non-performing | PCI - residential real estate
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans	[2]	0	0
Premium finance receivables | Commercial insurance loans
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		2,374,921	2,350,833
Premium finance receivables | Life insurance loans
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		2,593,204	1,884,092
Premium finance receivables | PCI - life insurance loans
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans	[1],[2]	368,292	393,479
Premium finance receivables | Performing | Commercial insurance loans
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		2,350,066	2,330,463
Premium finance receivables | Performing | Life insurance loans
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		2,593,204	1,884,092
Premium finance receivables | Performing | PCI - life insurance loans
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans	[2]	368,292	393,479
Premium finance receivables | Non-performing | Commercial insurance loans
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		24,855	20,370
Premium finance receivables | Non-performing | Life insurance loans
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		0	0
Premium finance receivables | Non-performing | PCI - life insurance loans
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans	[2]	0	0
Consumer and other
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		146,376	151,012
Consumer and other | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		145,963	150,617
Consumer and other | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		$ 413	$ 395

[1] PCI loans represent loans acquired with evidence of credit quality deterioration since origination, in accordance with ASC 310-30. Loan agings are based upon contractually required payments. See Note 4 - Loans for further discussion of these purchased loans.

[2] PCI loans represent loans acquired with evidence of credit quality deterioration since origination, in accordance with ASC 310-30. See Note 4 - Loans for further discussion of these purchased loans.