Loans and Leases (Details 2) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	$ 129,019	$ 83,621
Non Purchased Credit Impaired Loans and Leases [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	129,019	83,621
Loans held for investment, net	14,289,209	11,591,641
Non Purchased Credit Impaired Loans and Leases [Member] | Performing Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	14,160,190	11,508,020
Non Purchased Credit Impaired Loans and Leases [Member] | Mortgages [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	57,277	37,612
Loans held for investment, net	5,688,063	5,336,930
Non Purchased Credit Impaired Loans and Leases [Member] | Mortgages [Member] | Performing Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	5,630,786	5,299,318
Non Purchased Credit Impaired Loans and Leases [Member] | Mortgages [Member] | Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	52,363	32,223
Loans held for investment, net	4,551,958	4,429,886
Non Purchased Credit Impaired Loans and Leases [Member] | Mortgages [Member] | Commercial Real Estate [Member] | Performing Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	4,499,595	4,397,663
Non Purchased Credit Impaired Loans and Leases [Member] | Mortgages [Member] | Residential Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	4,914	5,389
Loans held for investment, net	1,136,105	907,044
Non Purchased Credit Impaired Loans and Leases [Member] | Mortgages [Member] | Residential Real Estate [Member] | Performing Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	1,131,191	901,655
Non Purchased Credit Impaired Loans and Leases [Member] | Real Estate Construction [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	372	1,559
Loans held for investment, net	527,720	310,765
Non Purchased Credit Impaired Loans and Leases [Member] | Real Estate Construction [Member] | Performing Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	527,348	309,206
Non Purchased Credit Impaired Loans and Leases [Member] | Real Estate Construction [Member] | Commercial Real Estate Construction Loan Receivable [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	0	1,178
Loans held for investment, net	343,360	214,037
Non Purchased Credit Impaired Loans and Leases [Member] | Real Estate Construction [Member] | Commercial Real Estate Construction Loan Receivable [Member] | Performing Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	343,360	212,859
Non Purchased Credit Impaired Loans and Leases [Member] | Real Estate Construction [Member] | Residential Real Estate Construction Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	372	381
Loans held for investment, net	184,360	96,728
Non Purchased Credit Impaired Loans and Leases [Member] | Real Estate Construction [Member] | Residential Real Estate Construction Financing Receivable [Member] | Performing Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	183,988	96,347
Non Purchased Credit Impaired Loans and Leases [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	69,839	40,965
Loans held for investment, net	7,952,577	5,842,463
Non Purchased Credit Impaired Loans and Leases [Member] | Commercial Portfolio Segment [Member] | Performing Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	7,882,738	5,801,498
Non Purchased Credit Impaired Loans and Leases [Member] | Commercial Portfolio Segment [Member] | Cash Flow [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	15,800	19,810
Loans held for investment, net	3,062,268	2,638,936
Non Purchased Credit Impaired Loans and Leases [Member] | Commercial Portfolio Segment [Member] | Cash Flow [Member] | Performing Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	3,046,468	2,619,126
Non Purchased Credit Impaired Loans and Leases [Member] | Commercial Portfolio Segment [Member] | Asset Based [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	2,505	10,024
Loans held for investment, net	2,547,533	2,234,038
Non Purchased Credit Impaired Loans and Leases [Member] | Commercial Portfolio Segment [Member] | Asset Based [Member] | Performing Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	2,545,028	2,224,014
Non Purchased Credit Impaired Loans and Leases [Member] | Commercial Portfolio Segment [Member] | Equipment Finance Commercial Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	51,410	11,131
Loans held for investment, net	890,349	969,489
Non Purchased Credit Impaired Loans and Leases [Member] | Commercial Portfolio Segment [Member] | Equipment Finance Commercial Financing Receivable [Member] | Performing Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	838,939	958,358
Non Purchased Credit Impaired Loans and Leases [Member] | Commercial Portfolio Segment [Member] | Venture Capital Loans [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	124	0
Loans held for investment, net	1,452,427	0
Non Purchased Credit Impaired Loans and Leases [Member] | Commercial Portfolio Segment [Member] | Venture Capital Loans [Member] | Performing Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	1,452,303	0
Non Purchased Credit Impaired Loans and Leases [Member] | Consumer Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	1,531	3,485
Loans held for investment, net	120,849	101,483
Non Purchased Credit Impaired Loans and Leases [Member] | Consumer Portfolio Segment [Member] | Performing Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	$ 119,318	$ 97,998