IMPAIRED LOANS AND ALLOWANCE FOR LOAN LOSSES - Loan Portfolio and Related Allowance (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Carrying Value
Individually Evaluated for Impairment	$ 29,982	$ 32,718
Collectively Evaluated for Impairment	24,162	20,946
Total	3,374,548	2,866,540
Associated Allowance
Individually Evaluated for Impairment	2,070	2,454
Collectively Evaluated for Impairment	3,344,566	2,833,822
Total	26,232	23,400
PCI Loans [Member]
Carrying Value
Individually Evaluated for Impairment	10,443	12,996
Associated Allowance
Individually Evaluated for Impairment	0	0
Construction and Land Development [Member]
Carrying Value
Individually Evaluated for Impairment	686	277
Collectively Evaluated for Impairment	1,521	1,219
Total	245,035	160,116
Associated Allowance
Individually Evaluated for Impairment	91	0
Collectively Evaluated for Impairment	244,349	159,839
Total	1,612	1,219
Construction and Land Development [Member] \| PCI Loans [Member]
Carrying Value
Individually Evaluated for Impairment	116	114
Associated Allowance
Individually Evaluated for Impairment	0	0
Commercial Real Estate [Member]
Carrying Value
Individually Evaluated for Impairment	8,362	10,204
Collectively Evaluated for Impairment	9,684	8,878
Total	1,469,117	1,346,036
Associated Allowance
Individually Evaluated for Impairment	222	395
Collectively Evaluated for Impairment	1,460,755	1,335,832
Total	9,906	9,273
Commercial Real Estate [Member] \| PCI Loans [Member]
Carrying Value
Individually Evaluated for Impairment	8,975	11,257
Associated Allowance
Individually Evaluated for Impairment	0	0
Residential Real Estate [Member]
Carrying Value
Individually Evaluated for Impairment	19,371	22,038
Collectively Evaluated for Impairment	5,946	5,424
Total	940,641	836,288
Associated Allowance
Individually Evaluated for Impairment	1,188	2,059
Collectively Evaluated for Impairment	921,270	814,250
Total	7,134	7,483
Residential Real Estate [Member] \| PCI Loans [Member]
Carrying Value
Individually Evaluated for Impairment	528	684
Associated Allowance
Individually Evaluated for Impairment	0	0
Commercial And Financial [Member]
Carrying Value
Individually Evaluated for Impairment	1,156	199
Collectively Evaluated for Impairment	5,468	3,636
Total	534,633	369,648
Associated Allowance
Individually Evaluated for Impairment	521	0
Collectively Evaluated for Impairment	533,477	369,449
Total	5,989	3,636
Commercial And Financial [Member] \| PCI Loans [Member]
Carrying Value
Individually Evaluated for Impairment	824	941
Associated Allowance
Individually Evaluated for Impairment	0	0
Consumer [Member]
Carrying Value
Individually Evaluated for Impairment	407	0
Collectively Evaluated for Impairment	1,543	1,789
Total	185,122	154,452
Associated Allowance
Individually Evaluated for Impairment	48	0
Collectively Evaluated for Impairment	184,715	154,452
Total	1,591	1,789
Consumer [Member] \| PCI Loans [Member]
Carrying Value
Individually Evaluated for Impairment	0	0
Associated Allowance
Individually Evaluated for Impairment	$ 0	$ 0

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A valuation allowance for financing receivables that are expected to be uncollectible.

+ References

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

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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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