Loans and Allowance for Loan Losses - Loan Portfolio by Categories (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, gross	$ 11,720,000	$ 10,780,000
Loans acquired, net of discount and allowance	3,292,783	5,074,076
Total loans	11,723,171	10,779,685
Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, gross	8,430,388	5,705,609
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, gross	405,470	465,516
Consumer \| Credit cards
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, gross	204,173	185,422
Consumer \| Other consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, gross	201,297	280,094
Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, gross	5,966,453	4,239,612
Real Estate \| Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, gross	1,300,723	614,155
Real Estate \| Single family residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, gross	1,440,443	1,094,633
Real Estate \| Other commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, gross	3,225,287	2,530,824
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, gross	1,939,423	973,519
Commercial \| Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, gross	1,774,909	825,217
Commercial \| Agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, gross	164,514	148,302
Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, gross	$ 119,042	$ 26,962

Loans acquired which are not covered by FDIC loss share agreements, net of discount.

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- Definition

Loans and leases receivable, net of deferred income covered and not covered

+ References

No definition available.

+ Details

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- Definition

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+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

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