INCOME TAXES - Provision for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Current federal tax expense	$ 10,542	$ 6,097	$ 5,288
Deferred federal tax (benefit) expense	(4,647)	(319)	(683)
Revaluation of net deferred tax assets due to change in U.S. federal statutory income tax rate	0	0	(6)
Total	$ 5,895	$ 5,778	$ 4,599