Loans and Leases (Details 3) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	$ 22,941,548	$ 19,083,377
Financing Receivable, Nonaccrual	61,174	91,163
Mortgages [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	11,178,720	7,899,936
Financing Receivable, Nonaccrual	39,832	45,557
Real Estate Construction [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	3,437,127	3,360,281
Financing Receivable, Nonaccrual	4,715	315
Commercial Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	7,868,051	7,502,905
Financing Receivable, Nonaccrual	16,213	44,902
Consumer Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	457,650	320,255
Financing Receivable, Nonaccrual	414	389
Classified [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	116,104	265,262
Classified [Member] | Mortgages [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	79,906	100,310
Classified [Member] | Real Estate Construction [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	4,715	42,558
Classified [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	31,044	121,932
Classified [Member] | Consumer Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	439	462
Special Mention [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	391,611	721,285
Special Mention [Member] | Mortgages [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	211,657	323,846
Special Mention [Member] | Real Estate Construction [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	69,447	108,351
Special Mention [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	108,666	286,356
Special Mention [Member] | Consumer Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	1,841	2,732
Pass [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	22,433,833	18,096,830
Pass [Member] | Mortgages [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	10,887,157	7,475,780
Pass [Member] | Real Estate Construction [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	3,362,965	3,209,372
Pass [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	7,728,341	7,094,617
Pass [Member] | Consumer Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	455,370	317,061
Performing Financing Receivable [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	22,880,374	18,992,214
Performing Financing Receivable [Member] | Mortgages [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	11,138,888	7,854,379
Performing Financing Receivable [Member] | Real Estate Construction [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	3,432,412	3,359,966
Performing Financing Receivable [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	7,851,838	7,458,003
Performing Financing Receivable [Member] | Consumer Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	457,236	319,866
Asset Based [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	4,075,477	3,429,283
Financing Receivable, Nonaccrual	1,464	2,679
Asset Based [Member] | Classified [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	4,591	27,867
Asset Based [Member] | Special Mention [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	78,305	153,301
Asset Based [Member] | Pass [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	3,992,581	3,248,115
Asset Based [Member] | Performing Financing Receivable [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	4,074,013	3,426,604
Venture Capital Loans [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	2,320,593	1,698,508
Financing Receivable, Nonaccrual	2,799	1,980
Venture Capital Loans [Member] | Classified [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	4,794	6,508
Venture Capital Loans [Member] | Special Mention [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	14,833	118,125
Venture Capital Loans [Member] | Pass [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	2,300,966	1,573,875
Venture Capital Loans [Member] | Performing Financing Receivable [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	2,317,794	1,696,528
Other Commercial [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	1,471,981	2,375,114
Financing Receivable, Nonaccrual	11,950	40,243
Other Commercial [Member] | Classified [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	21,659	87,557
Other Commercial [Member] | Special Mention [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	15,528	14,930
Other Commercial [Member] | Pass [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	1,434,794	2,272,627
Other Commercial [Member] | Performing Financing Receivable [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	1,460,031	2,334,871
Commercial Real Estate Construction Loan Receivable [Member] | Real Estate Construction [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	832,591	1,117,121
Financing Receivable, Nonaccrual	0	315
Commercial Real Estate Construction Loan Receivable [Member] | Classified [Member] | Real Estate Construction [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	0	42,558
Commercial Real Estate Construction Loan Receivable [Member] | Special Mention [Member] | Real Estate Construction [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	67,727	107,592
Commercial Real Estate Construction Loan Receivable [Member] | Pass [Member] | Real Estate Construction [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	764,864	966,971
Commercial Real Estate Construction Loan Receivable [Member] | Performing Financing Receivable [Member] | Real Estate Construction [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	832,591	1,116,806
Residential Real Estate Construction Financing Receivable [Member] | Real Estate Construction [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	2,604,536	2,243,160
Financing Receivable, Nonaccrual	4,715	0
Residential Real Estate Construction Financing Receivable [Member] | Classified [Member] | Real Estate Construction [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	4,715	0
Residential Real Estate Construction Financing Receivable [Member] | Special Mention [Member] | Real Estate Construction [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	1,720	759
Residential Real Estate Construction Financing Receivable [Member] | Pass [Member] | Real Estate Construction [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	2,598,101	2,242,401
Residential Real Estate Construction Financing Receivable [Member] | Performing Financing Receivable [Member] | Real Estate Construction [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	2,599,821	2,243,160
Commercial Real Estate [Member] | Mortgages [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	3,762,299	4,096,671
Financing Receivable, Nonaccrual	27,540	43,731
Commercial Real Estate [Member] | Classified [Member] | Mortgages [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	62,206	91,543
Commercial Real Estate [Member] | Special Mention [Member] | Mortgages [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	191,809	262,462
Commercial Real Estate [Member] | Pass [Member] | Mortgages [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	3,508,284	3,742,666
Commercial Real Estate [Member] | Performing Financing Receivable [Member] | Mortgages [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	3,734,759	4,052,940
Residential Real Estate [Member] | Mortgages [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	7,416,421	3,803,265
Financing Receivable, Nonaccrual	12,292	1,826
Residential Real Estate [Member] | Classified [Member] | Mortgages [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	17,700	8,767
Residential Real Estate [Member] | Special Mention [Member] | Mortgages [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	19,848	61,384
Residential Real Estate [Member] | Pass [Member] | Mortgages [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	7,378,873	3,733,114
Residential Real Estate [Member] | Performing Financing Receivable [Member] | Mortgages [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment, net	$ 7,404,129	$ 3,801,439