Loans and Leases (Details 10) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period	$ 138,785	$ 132,472
Charge-offs	(20,205)	(3,465)
Recoveries	1,095	3,274
Net charge-offs	(19,110)	(191)
Provision	98,000	4,000
Balance, end of period	221,292	136,281
Amount of the allowance applicable to loans and leases:
Individually evaluated	6,692	6,201
Collectively evaluated	214,600	130,080
The ending balance of the loan and lease portfolio is composed of loans and leases:
Individually evaluated	99,997	101,000
Collectively evaluated	19,645,308	18,206,697
Loans held for investment, net	19,745,305	18,307,697	$ 18,846,872
Financing Receivable, Allowance for Loan and Lease Losses, Effect of Change in Method	3,617
Real Estate Mortgage
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period	44,575	46,021
Charge-offs	(500)	(196)
Recoveries	124	143
Net charge-offs	(376)	(53)
Provision	41,865	(214)
Balance, end of period	91,372	45,754
Amount of the allowance applicable to loans and leases:
Individually evaluated	230	270
Collectively evaluated	91,142	45,484
The ending balance of the loan and lease portfolio is composed of loans and leases:
Individually evaluated	25,901	23,908
Collectively evaluated	7,983,043	8,135,550
Loans held for investment, net	8,008,944	8,159,458	7,972,747
Financing Receivable, Allowance for Loan and Lease Losses, Effect of Change in Method	5,308
Real Estate Construction and Land
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period	30,544	28,209
Charge-offs	0	0
Recoveries	0	0
Net charge-offs	0	0
Provision	18,221	(1,001)
Balance, end of period	40,173	27,208
Amount of the allowance applicable to loans and leases:
Individually evaluated	0	0
Collectively evaluated	40,173	27,208
The ending balance of the loan and lease portfolio is composed of loans and leases:
Individually evaluated	1,816	5,432
Collectively evaluated	2,878,437	2,346,292
Loans held for investment, net	2,880,253	2,351,724	2,737,802
Financing Receivable, Allowance for Loan and Lease Losses, Effect of Change in Method	(8,592)
Commercial
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period	61,528	56,360
Charge-offs	(19,232)	(3,003)
Recoveries	955	3,106
Net charge-offs	(18,277)	103
Provision	37,459	5,033
Balance, end of period	87,570	61,496
Amount of the allowance applicable to loans and leases:
Individually evaluated	6,462	5,931
Collectively evaluated	81,108	55,565
The ending balance of the loan and lease portfolio is composed of loans and leases:
Individually evaluated	72,280	71,660
Collectively evaluated	8,353,944	7,352,694
Loans held for investment, net	8,426,224	7,424,354	7,695,496
Financing Receivable, Allowance for Loan and Lease Losses, Effect of Change in Method	6,860
Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period	2,138	1,882
Charge-offs	(473)	(266)
Recoveries	16	25
Net charge-offs	(457)	(241)
Provision	455	182
Balance, end of period	2,177	1,823
Amount of the allowance applicable to loans and leases:
Individually evaluated	0	0
Collectively evaluated	2,177	1,823
The ending balance of the loan and lease portfolio is composed of loans and leases:
Individually evaluated	0	0
Collectively evaluated	429,884	372,161
Loans held for investment, net	429,884	$ 372,161	$ 440,827
Financing Receivable, Allowance for Loan and Lease Losses, Effect of Change in Method	$ 41

Financing Receivable, Allowance for Credit Loss, Additional Information, Portfolio Composition [Abstract]

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Financing Receivable, Allowance for Loan and Lease Losses, Effect of Change in Method

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Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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Amount, after recoveries, of loans and leases that have been written-off.

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount of expense related to estimated loss from loan and lease transactions.

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