Loans and Allowance for Loan Losses - Loan Portfolio by Categories (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Loans and Leases Receivable Disclosure [Line Items]
Loans	$ 13,130,000	$ 11,720,000
Loans acquired, net of discount and allowance	3,864,516	3,292,783
Total loans	13,127,013	11,723,171
Loans, Excluding Acquired Loans
Loans and Leases Receivable Disclosure [Line Items]
Loans	9,262,497	8,430,388
Consumer
Loans and Leases Receivable Disclosure [Line Items]
Loans	395,364	405,470
Consumer \| Credit cards
Loans and Leases Receivable Disclosure [Line Items]
Loans	187,919	204,173
Consumer \| Other consumer
Loans and Leases Receivable Disclosure [Line Items]
Loans	207,445	201,297
Real Estate
Loans and Leases Receivable Disclosure [Line Items]
Loans	6,516,150	5,966,453
Real Estate \| Construction
Loans and Leases Receivable Disclosure [Line Items]
Loans	1,540,352	1,300,723
Real Estate \| Single family residential
Loans and Leases Receivable Disclosure [Line Items]
Loans	1,444,525	1,440,443
Real Estate \| Other commercial
Loans and Leases Receivable Disclosure [Line Items]
Loans	3,531,273	3,225,287
Commercial
Loans and Leases Receivable Disclosure [Line Items]
Loans	2,063,617	1,939,423
Commercial \| Commercial
Loans and Leases Receivable Disclosure [Line Items]
Loans	1,871,695	1,774,909
Commercial \| Agricultural
Loans and Leases Receivable Disclosure [Line Items]
Loans	191,922	164,514
Other
Loans and Leases Receivable Disclosure [Line Items]
Loans	$ 287,366	$ 119,042

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

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+ 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=118952595&loc=d3e4428-111522

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