OTHER COMPREHENSIVE INCOME (LOSS)-AOCI (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance, January 1	$ (23,454)	$ (14,704)
Change in other comprehensive income before reclassification	14,818	(7,467)
Amounts reclassified from accumulated other comprehensive income	1,135	1,083
Net current period other comprehensive income (loss)	15,953	(6,384)
Ending balance, December 31	(7,501)	(23,454)
Unrealized Gains and Losses on Available-for-Sale Securities
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance, January 1	(6,105)	2,258
Change in other comprehensive income before reclassification	21,031	(8,859)
Amounts reclassified from accumulated other comprehensive income	(33)	(2)
Net current period other comprehensive income (loss)	20,998	(8,861)
Ending balance, December 31	14,893	(6,105)
Retirement Plans
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance, January 1	(17,349)	(16,962)
Change in other comprehensive income before reclassification	(6,213)	1,392
Amounts reclassified from accumulated other comprehensive income	1,168	1,085
Net current period other comprehensive income (loss)	(5,045)	2,477
Ending balance, December 31	$ (22,394)	$ (17,349)

Accumulated Other Comprehensive Income (Loss) [Roll Forward]

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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