SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Cash flow reporting (Details) - USD ($)	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Cash collateral used in interest rate swap transactions	$ 0		$ 1,800,000
Supplemental disclosures of cash flow information:
Cash paid for taxes	6,750,000	$ 4,559,000
Cash paid for interest	4,171,000	4,694,000
Supplemental disclosures of non-cash flow information:
Operating lease right-of-use asset, increase	809,000
Operating lease right-to-use asset increased (decreased) exchange for lease liabilities	809,000	(617,000)
Change in liability for dividends accrued	$ 167,000	$ (755,000)