SIGNIFICANT ACCOUNTING POLICIES - Property and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Accounting Policies [Abstract]
Depreciation expense	$ 32,847	$ 33,618	$ 31,866
Capital expenditure commitments outstanding	1,800
Property, Plant and Equipment [Line Items]
Property and equipment, gross	511,108	483,701
Accumulated depreciation	(223,378)	(192,147)
Net property and equipment before construction in progress	287,730	291,554
Capital improvements in progress	88,298	48,764
Net property and equipment	$ 376,028	340,318
Maximum
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	40 years
Land, land easements and land improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 105,514	104,671
Land, land easements and land improvements | Minimum
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	0 years
Land, land easements and land improvements | Maximum
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	15 years
Buildings
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 37,177	36,101
Buildings | Minimum
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	20 years
Buildings | Maximum
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	40 years
Equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 227,824	216,347
Equipment | Minimum
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	3 years
Equipment | Maximum
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	40 years
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 20,619	19,896
Furniture and fixtures | Minimum
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	5 years
Furniture and fixtures | Maximum
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	10 years
Other
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 44	44
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 119,930	$ 106,642