Loans and Leases (Details 2) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	$ 127,655	$ 129,019
Loans and Leases Receivable, Net of Deferred Income	14,641,460	14,478,254
Non Purchased Credit Impaired Loans and Leases
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	127,655	129,019
Loans and Leases Receivable, Net of Deferred Income	14,504,580	14,289,209	$ 11,811,551
Performing Financing Receivable [Member] | Non Purchased Credit Impaired Loans and Leases
Financing Receivable, Impaired [Line Items]
Loans and Leases Receivable, Net of Deferred Income	14,376,925	14,160,190
Mortgage Loans on Real Estate | Non Purchased Credit Impaired Loans and Leases
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	33,421	57,277
Loans and Leases Receivable, Net of Deferred Income	5,563,380	5,688,063	5,410,431
Mortgage Loans on Real Estate | Performing Financing Receivable [Member] | Non Purchased Credit Impaired Loans and Leases
Financing Receivable, Impaired [Line Items]
Loans and Leases Receivable, Net of Deferred Income	5,529,959	5,630,786
Mortgage Loans on Real Estate | Commercial real estate | Non Purchased Credit Impaired Loans and Leases
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	29,183	52,363
Loans and Leases Receivable, Net of Deferred Income	4,466,406	4,551,958
Mortgage Loans on Real Estate | Commercial real estate | Performing Financing Receivable [Member] | Non Purchased Credit Impaired Loans and Leases
Financing Receivable, Impaired [Line Items]
Loans and Leases Receivable, Net of Deferred Income	4,437,223	4,499,595
Mortgage Loans on Real Estate | Residential Real Estate | Non Purchased Credit Impaired Loans and Leases
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	4,238	4,914
Loans and Leases Receivable, Net of Deferred Income	1,096,974	1,136,105
Mortgage Loans on Real Estate | Residential Real Estate | Performing Financing Receivable [Member] | Non Purchased Credit Impaired Loans and Leases
Financing Receivable, Impaired [Line Items]
Loans and Leases Receivable, Net of Deferred Income	1,092,736	1,131,191
Real Estate Construction | Non Purchased Credit Impaired Loans and Leases
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	368	372
Loans and Leases Receivable, Net of Deferred Income	696,233	527,720	348,739
Real Estate Construction | Performing Financing Receivable [Member] | Non Purchased Credit Impaired Loans and Leases
Financing Receivable, Impaired [Line Items]
Loans and Leases Receivable, Net of Deferred Income	695,865	527,348
Real Estate Construction | Commercial Real Estate Construction Loan Receivable | Non Purchased Credit Impaired Loans and Leases
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	0	0
Loans and Leases Receivable, Net of Deferred Income	414,466	343,360
Real Estate Construction | Commercial Real Estate Construction Loan Receivable | Performing Financing Receivable [Member] | Non Purchased Credit Impaired Loans and Leases
Financing Receivable, Impaired [Line Items]
Loans and Leases Receivable, Net of Deferred Income	414,466	343,360
Real Estate Construction | Residential Real Estate Construction Financing Receivable | Non Purchased Credit Impaired Loans and Leases
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	368	372
Loans and Leases Receivable, Net of Deferred Income	281,767	184,360
Real Estate Construction | Residential Real Estate Construction Financing Receivable | Performing Financing Receivable [Member] | Non Purchased Credit Impaired Loans and Leases
Financing Receivable, Impaired [Line Items]
Loans and Leases Receivable, Net of Deferred Income	281,399	183,988
Commercial Portfolio Segment | Non Purchased Credit Impaired Loans and Leases
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	93,652	69,839
Loans and Leases Receivable, Net of Deferred Income	8,032,333	7,952,577	5,966,102
Commercial Portfolio Segment | Performing Financing Receivable [Member] | Non Purchased Credit Impaired Loans and Leases
Financing Receivable, Impaired [Line Items]
Loans and Leases Receivable, Net of Deferred Income	7,938,681	7,882,738
Commercial Portfolio Segment | Cash Flow | Non Purchased Credit Impaired Loans and Leases
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	38,146	15,800
Loans and Leases Receivable, Net of Deferred Income	3,041,862	3,062,268
Commercial Portfolio Segment | Cash Flow | Performing Financing Receivable [Member] | Non Purchased Credit Impaired Loans and Leases
Financing Receivable, Impaired [Line Items]
Loans and Leases Receivable, Net of Deferred Income	3,003,716	3,046,468
Commercial Portfolio Segment | Asset Based | Non Purchased Credit Impaired Loans and Leases
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	1,986	2,505
Loans and Leases Receivable, Net of Deferred Income	2,682,264	2,547,533
Commercial Portfolio Segment | Asset Based | Performing Financing Receivable [Member] | Non Purchased Credit Impaired Loans and Leases
Financing Receivable, Impaired [Line Items]
Loans and Leases Receivable, Net of Deferred Income	2,680,278	2,545,028
Commercial Portfolio Segment | Venture Capital Loans | Non Purchased Credit Impaired Loans and Leases
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	1,088	124
Loans and Leases Receivable, Net of Deferred Income	1,661,267	1,452,427
Commercial Portfolio Segment | Venture Capital Loans | Performing Financing Receivable [Member] | Non Purchased Credit Impaired Loans and Leases
Financing Receivable, Impaired [Line Items]
Loans and Leases Receivable, Net of Deferred Income	1,660,179	1,452,303
Commercial Portfolio Segment | Equipment Finance Commercial Financing Receivable | Non Purchased Credit Impaired Loans and Leases
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	52,432	51,410
Loans and Leases Receivable, Net of Deferred Income	646,940	890,349
Commercial Portfolio Segment | Equipment Finance Commercial Financing Receivable | Performing Financing Receivable [Member] | Non Purchased Credit Impaired Loans and Leases
Financing Receivable, Impaired [Line Items]
Loans and Leases Receivable, Net of Deferred Income	594,508	838,939
Consumer Portfolio Segment | Non Purchased Credit Impaired Loans and Leases
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	214	1,531
Loans and Leases Receivable, Net of Deferred Income	212,634	120,849	$ 86,279
Consumer Portfolio Segment | Performing Financing Receivable [Member] | Non Purchased Credit Impaired Loans and Leases
Financing Receivable, Impaired [Line Items]
Loans and Leases Receivable, Net of Deferred Income	$ 212,420	$ 119,318