Loans and Leases (Details 1) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Delinquent loans in loan portfolio
30-89 Days Past Due	$ 9,788	$ 17,085
Loan Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	11,085	10,723
Financing Receivable, Past Due	20,873	27,808
Current	18,825,999	17,929,905
Loans held for investment, net	18,846,872	17,957,713
Mortgages [Member]
Delinquent loans in loan portfolio
30-89 Days Past Due	4,553	5,044
Loan Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	6,721	8,017
Financing Receivable, Past Due	11,274	13,061
Current	7,961,473	7,905,080
Loans held for investment, net	7,972,747	7,918,141
Real Estate Construction [Member]
Delinquent loans in loan portfolio
30-89 Days Past Due	1,429	1,527
Loan Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	0	442
Financing Receivable, Past Due	1,429	1,969
Current	2,736,373	2,231,687
Loans held for investment, net	2,737,802	2,233,656
Commercial Portfolio Segment [Member]
Delinquent loans in loan portfolio
30-89 Days Past Due	2,800	9,933
Loan Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	4,164	1,931
Financing Receivable, Past Due	6,964	11,864
Current	7,688,532	7,392,731
Loans held for investment, net	7,695,496	7,404,595
Consumer Portfolio Segment [Member]
Delinquent loans in loan portfolio
30-89 Days Past Due	1,006	581
Loan Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	200	333
Financing Receivable, Past Due	1,206	914
Current	439,621	400,407
Loans held for investment, net	440,827	401,321
Asset Based [Member] \| Commercial Portfolio Segment [Member]
Delinquent loans in loan portfolio
30-89 Days Past Due	19	47
Loan Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	0	646
Financing Receivable, Past Due	19	693
Current	3,748,388	3,304,728
Loans held for investment, net	3,748,407	3,305,421
Venture Capital Loans [Member] \| Commercial Portfolio Segment [Member]
Delinquent loans in loan portfolio
30-89 Days Past Due	0	4,705
Loan Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	0	0
Financing Receivable, Past Due	0	4,705
Current	2,179,422	2,034,043
Loans held for investment, net	2,179,422	2,038,748
Other Commercial [Member] \| Commercial Portfolio Segment [Member]
Delinquent loans in loan portfolio
30-89 Days Past Due	2,781	5,181
Loan Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	4,164	1,285
Financing Receivable, Past Due	6,945	6,466
Current	1,760,722	2,053,960
Loans held for investment, net	1,767,667	2,060,426
Commercial Real Estate Construction Loan Receivable [Member] \| Real Estate Construction [Member]
Delinquent loans in loan portfolio
30-89 Days Past Due	0	0
Loan Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	0	442
Financing Receivable, Past Due	0	442
Current	1,082,368	912,141
Loans held for investment, net	1,082,368	912,583
Residential Real Estate Construction Financing Receivable [Member] \| Real Estate Construction [Member]
Delinquent loans in loan portfolio
30-89 Days Past Due	1,429	1,527
Loan Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	0	0
Financing Receivable, Past Due	1,429	1,527
Current	1,654,005	1,319,546
Loans held for investment, net	1,655,434	1,321,073
Commercial Real Estate [Member] \| Mortgages [Member]
Delinquent loans in loan portfolio
30-89 Days Past Due	2,448	3,487
Loan Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	5,919	7,541
Financing Receivable, Past Due	8,367	11,028
Current	4,194,320	4,813,270
Loans held for investment, net	4,202,687	4,824,298
Residential Real Estate [Member] \| Mortgages [Member]
Delinquent loans in loan portfolio
30-89 Days Past Due	2,105	1,557
Loan Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	802	476
Financing Receivable, Past Due	2,907	2,033
Current	3,767,153	3,091,810
Loans held for investment, net	$ 3,770,060	$ 3,093,843

Financing receivable recorded investment 30 to 89 days past due.

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- Definition

Loan Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due - replaces Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due

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Receivables, Past Due [Abstract]

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Amount of financing receivable not past due.

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Amount of financing receivable past due.

+ References

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- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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