DEPOSITS - Maturity of deposits (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Summary of certificate accounts by maturity
Within 1 year	$ 717,594
Over 1 year to 2 years	138,549
Over 2 years to 3 years	23,277
Over 3 years to 4 years	8,033
Over 4 years to 5 years	1,004
Total certificate deposits	888,457
Less unaccreted acquisition discount	(1,379)
Total certificate deposits, net	$ 887,078	$ 887,523
Summary of certificate accounts by maturity
Within 1 year	2.18%
Over 1 year to 2 years	2.02%
Over 2 years to 3 years	1.93%
Over 3 years to 4 years	2.06%
Over 4 years to 5 years	1.66%
Weighted average interest rate	2.15%

Amount of gross time deposits, prior to any adjustments.

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- Definition

Amount of unaccreted acquisition discount included in time deposit liabilities.

+ References

No definition available.

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- Definition

Total weighted average interest rate for time deposits held by the entity.

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No definition available.

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- Definition

Amount of time deposits maturing in the next rolling twelve months following the latest balance sheet. Time deposits include, but are not limited to, certificates of deposits. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

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- Definition

Amount of time deposits maturing in the fifth rolling twelve months following the latest balance sheet. Time deposits include, but are not limited to, certificates of deposits. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

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Amount of time deposits maturing in the fourth rolling twelve months following the latest balance sheet. Time deposits include, but are not limited to, certificates of deposits. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of time deposits maturing in the third rolling twelve months following the latest balance sheet. Time deposits include, but are not limited to, certificates of deposits. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

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Amount of time deposits maturing in the second rolling twelve months following the latest balance sheet. Time deposits include, but are not limited to, certificates of deposits. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of time deposit liabilities, including certificates of deposit.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 405
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=116652737&loc=d3e64164-112818

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.12)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Weighted average interest rate for time deposits held by the entity with maturities greater than four years, but five years or less.

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Weighted average interest rate for time deposits held by the entity with maturities greater than three years, but four years or less.

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Weighted average interest rate for time deposits held by the entity with maturities of one year or less.

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Weighted average interest rate for time deposits held by the entity with maturities greater than two years, but three years or less.

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Weighted average interest rate for time deposits held by the entity with maturities greater than one year, but two years or less.

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