Allowance for Loan Losses (Details 2) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Investment in loans, net of unearned income on impairment methodology
Individually evaluated for impairment	$ 27,992	$ 36,627
Collectively evaluated for impairment	5,902,959	5,040,670
Loans, net of unearned income	6,202,709	5,413,462
Receivables Acquired with Deteriorated Credit Quality
Investment in loans, net of unearned income on impairment methodology
Acquired with deteriorated credit quality	271,758	336,165
Commercial, financial, agricultural
Investment in loans, net of unearned income on impairment methodology
Individually evaluated for impairment	1,886	370
Collectively evaluated for impairment	703,610	619,978
Loans, net of unearned income	717,490	636,837
Commercial, financial, agricultural \| Receivables Acquired with Deteriorated Credit Quality
Investment in loans, net of unearned income on impairment methodology
Acquired with deteriorated credit quality	11,994	16,489
Real estate – construction
Investment in loans, net of unearned income on impairment methodology
Individually evaluated for impairment	662	2,698
Collectively evaluated for impairment	551,177	352,218
Loans, net of unearned income	552,679	357,665
Real estate – construction \| Receivables Acquired with Deteriorated Credit Quality
Investment in loans, net of unearned income on impairment methodology
Acquired with deteriorated credit quality	840	2,749
Real estate – 1-4 family mortgage
Investment in loans, net of unearned income on impairment methodology
Individually evaluated for impairment	12,088	16,650
Collectively evaluated for impairment	1,794,137	1,627,024
Loans, net of unearned income	1,878,177	1,735,323
Real estate – 1-4 family mortgage \| Receivables Acquired with Deteriorated Credit Quality
Investment in loans, net of unearned income on impairment methodology
Acquired with deteriorated credit quality	71,952	91,649
Real estate – commercial mortgage
Investment in loans, net of unearned income on impairment methodology
Individually evaluated for impairment	13,079	16,819
Collectively evaluated for impairment	2,700,829	2,294,300
Loans, net of unearned income	2,898,895	2,533,729
Real estate – commercial mortgage \| Receivables Acquired with Deteriorated Credit Quality
Investment in loans, net of unearned income on impairment methodology
Acquired with deteriorated credit quality	184,987	222,610
Installment loans to individuals
Investment in loans, net of unearned income on impairment methodology
Individually evaluated for impairment	277	90
Collectively evaluated for impairment	153,206	147,150
Loans, net of unearned income	155,468	149,908
Installment loans to individuals \| Receivables Acquired with Deteriorated Credit Quality
Investment in loans, net of unearned income on impairment methodology
Acquired with deteriorated credit quality	$ 1,985	$ 2,668

Investment in loans, net of unearned income on impairment methodology.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

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

+ 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=65884687&loc=d3e4428-111522

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5074-111524

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Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.3)
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