Purchased Loans - Summary of Purchased Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Summary of loans
Gross loans	$ 9,091,181	$ 9,086,256
Unearned income	(2,888)	(3,127)
Loans, net of unearned income	9,088,293	9,083,129
Purchased loans
Summary of loans
Gross loans	2,522,694	2,693,417
Unearned income	0	0
Loans, net of unearned income	2,522,694	2,693,417
Commercial, financial, agricultural
Summary of loans
Gross loans	1,308,457	1,295,912
Loans, net of unearned income	1,308,457	1,295,912
Commercial, financial, agricultural \| Purchased loans
Summary of loans
Gross loans	387,376	420,263
Loans, net of unearned income	387,376	420,263
Real estate – construction
Summary of loans
Gross loans	741,073	740,668
Loans, net of unearned income	741,073	740,668
Real estate – construction \| Purchased loans
Summary of loans
Gross loans	89,954	105,149
Loans, net of unearned income	89,954	105,149
Real estate – 1-4 family mortgage
Summary of loans
Gross loans	2,769,173	2,795,343
Loans, net of unearned income	2,769,173	2,795,343
Real estate – 1-4 family mortgage \| Purchased loans
Summary of loans
Gross loans	654,265	707,453
Loans, net of unearned income	654,265	707,453
Real estate – commercial mortgage
Summary of loans
Gross loans	4,083,632	4,051,509
Loans, net of unearned income	4,083,632	4,051,509
Real estate – commercial mortgage \| Purchased loans
Summary of loans
Gross loans	1,357,446	1,423,144
Loans, net of unearned income	1,357,446	1,423,144
Installment loans to individuals
Summary of loans
Gross loans	127,307	137,832
Loans, net of unearned income	185,958	199,697
Installment loans to individuals \| Purchased loans
Summary of loans
Gross loans	33,653	37,408
Loans, net of unearned income	$ 33,653	$ 37,408

Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7)
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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.

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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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