INCOME TAXES - Change in net deferred tax assets and liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
INCOME TAXES
Unrealized (gains) losses recognized in comprehensive income	$ (830)	$ 288
Pension obligation of the defined benefit plan not yet recognized in income	1,348	51	$ (442)
Deferred provision for income taxes	(179)	(2,665)	(1,679)
Net decrease	339	(2,326)
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount	$ 0	$ 0	$ 2,624

Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to increase (decrease) in the income tax rates.

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The increase (decrease) during the reporting period in the account that represents the temporary difference that results from Income or Loss that is recognized for accounting purposes but not for tax purposes and vice versa.

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Amount of tax expense (benefit), after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities, attributable to parent entity. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount, after reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income for defined benefit plan, attributable to parent.

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