LEASES - Supplemental Balance Sheet Information (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Operating leases:
Operating lease right-of-use assets	$ 22,243,000	$ 23,116,000
Short-term lease liabilities, included in Other accrued liabilities	4,466,000	4,789,000
Long-term lease liabilities	17,947,000	18,424,000
Total operating lease liabilities	22,413,000	23,213,000
Finance leases:
Property, plant and equipment	240,000	456,000
Accumulated depreciation	(30,000)	(143,000)
Property, plant and equipment, net	210,000	313,000
Short-term lease liabilities, included in debt	0	35,000
Total finance lease liabilities	$ 0	$ 35,000
Weighted average remaining lease term (in years):
Operating leases	6 years 3 months 18 days	7 years 1 month 6 days
Finance leases	28 years 8 months 12 days	20 years 4 months 24 days
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:OtherAccruedLiabilitiesCurrent	us-gaap:OtherAccruedLiabilitiesCurrent
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	us-gaap:PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization	us-gaap:PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization
Finance Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:LongTermDebtAndCapitalLeaseObligationsCurrent	us-gaap:LongTermDebtAndCapitalLeaseObligationsCurrent