LOANS - Aging Status of recorded investment (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Aging Status of recorded investment
Total loans	$ 3,184,063	$ 2,319,976
Non-PCI loans
Aging Status of recorded investment
Nonaccrual Loans	24,991	16,871
Total Past Due	38,769	30,043
Current	3,115,286	2,261,677
Total loans	3,154,055	2,291,720
Non-PCI loans \| 31-59 Days Past Due
Aging Status of recorded investment
Past Due	7,666	9,241
Non-PCI loans \| 60-89 Days Past Due
Aging Status of recorded investment
Past Due	5,900	1,526
Non-PCI loans \| Accruing Loans past Due 90 Days or More
Aging Status of recorded investment
Past Due	212	2,405
Commercial loan portfolio \| Non-PCI loans
Aging Status of recorded investment
Total loans	2,196,456	1,583,380
Other loan portfolio \| Non-PCI loans
Aging Status of recorded investment
Total loans	957,599	708,340
Commercial \| Commercial loan portfolio
Aging Status of recorded investment
Total loans	571,111	457,827
Commercial \| Commercial loan portfolio \| Non-PCI loans
Aging Status of recorded investment
Nonaccrual Loans	2,989	3,559
Total Past Due	8,925	9,401
Current	559,930	444,909
Total loans	568,855	454,310
Commercial \| Commercial loan portfolio \| Non-PCI loans \| 31-59 Days Past Due
Aging Status of recorded investment
Past Due	3,114	3,326
Commercial \| Commercial loan portfolio \| Non-PCI loans \| 60-89 Days Past Due
Aging Status of recorded investment
Past Due	2,709	138
Commercial \| Commercial loan portfolio \| Non-PCI loans \| Accruing Loans past Due 90 Days or More
Aging Status of recorded investment
Past Due	113	2,378
Commercial real estate \| Commercial loan portfolio
Aging Status of recorded investment
Total loans	1,470,487	969,615
Commercial real estate \| Commercial loan portfolio \| Non-PCI loans
Aging Status of recorded investment
Nonaccrual Loans	16,277	7,145
Total Past Due	18,790	8,580
Current	1,437,282	955,315
Total loans	1,456,072	963,895
Commercial real estate \| Commercial loan portfolio \| Non-PCI loans \| 31-59 Days Past Due
Aging Status of recorded investment
Past Due	823	648
Commercial real estate \| Commercial loan portfolio \| Non-PCI loans \| 60-89 Days Past Due
Aging Status of recorded investment
Past Due	1,690	787
Construction and land development \| Commercial loan portfolio
Aging Status of recorded investment
Total loans	176,098	177,325
Construction and land development \| Commercial loan portfolio \| Non-PCI loans
Aging Status of recorded investment
Nonaccrual Loans		21
Total Past Due	1,012	21
Current	170,517	165,154
Total loans	171,529	165,175
Construction and land development \| Commercial loan portfolio \| Non-PCI loans \| 31-59 Days Past Due
Aging Status of recorded investment
Past Due	1,012
Residential real estate \| Other loan portfolio
Aging Status of recorded investment
Total loans	428,464	253,713
Residential real estate \| Other loan portfolio \| Non-PCI loans
Aging Status of recorded investment
Nonaccrual Loans	4,621	4,629
Total Past Due	5,542	8,114
Current	414,363	239,042
Total loans	419,905	247,156
Residential real estate \| Other loan portfolio \| Non-PCI loans \| 31-59 Days Past Due
Aging Status of recorded investment
Past Due	408	3,472
Residential real estate \| Other loan portfolio \| Non-PCI loans \| 60-89 Days Past Due
Aging Status of recorded investment
Past Due	416	13
Residential real estate \| Other loan portfolio \| Non-PCI loans \| Accruing Loans past Due 90 Days or More
Aging Status of recorded investment
Past Due	97
Consumer \| Other loan portfolio
Aging Status of recorded investment
Total loans	335,902	270,017
Consumer \| Other loan portfolio \| Non-PCI loans
Aging Status of recorded investment
Nonaccrual Loans	252	187
Total Past Due	3,311	2,502
Current	332,382	267,203
Total loans	335,693	269,705
Consumer \| Other loan portfolio \| Non-PCI loans \| 31-59 Days Past Due
Aging Status of recorded investment
Past Due	1,972	1,701
Consumer \| Other loan portfolio \| Non-PCI loans \| 60-89 Days Past Due
Aging Status of recorded investment
Past Due	1,085	588
Consumer \| Other loan portfolio \| Non-PCI loans \| Accruing Loans past Due 90 Days or More
Aging Status of recorded investment
Past Due	2	26
Lease financing \| Other loan portfolio
Aging Status of recorded investment
Total loans	202,001	191,479
Lease financing \| Other loan portfolio \| Non-PCI loans
Aging Status of recorded investment
Nonaccrual Loans	852	1,330
Total Past Due	1,189	1,425
Current	200,812	190,054
Total loans	202,001	191,479
Lease financing \| Other loan portfolio \| Non-PCI loans \| 31-59 Days Past Due
Aging Status of recorded investment
Past Due	$ 337	94
Lease financing \| Other loan portfolio \| Non-PCI loans \| Accruing Loans past Due 90 Days or More
Aging Status of recorded investment
Past Due		$ 1

Recorded investment in financing receivables that are past due at the balance sheet date, including nonaccrual loans.

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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. Includes loans and leases covered under loss sharing agreements.

+ References

No definition available.

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- Definition

Financing receivables that are current.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7A
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953401-111524

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- Definition

Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5111-111524

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- Definition

Recorded Investment in financing receivables that are past due at the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

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-Name Accounting Standards Codification
-Topic 310
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-Section 50
-Paragraph 7A
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953401-111524

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