SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Property and Equipment
Gross property and equipment	$ 834,425	$ 802,274
Less accumulated depreciation and amortization	(253,618)	(229,767)
Property and equipment, net	580,807	572,507
Land
Property and Equipment
Gross property and equipment	32,986	32,986
Land improvements
Property and Equipment
Gross property and equipment	9,898	9,847
Buildings
Property and Equipment
Gross property and equipment	474,571	471,819
Building improvements
Property and Equipment
Gross property and equipment	55,432	33,681
Furniture and equipment
Property and Equipment
Gross property and equipment	235,233	229,052
Construction in progress
Property and Equipment
Gross property and equipment	8,211	6,257
Right of use assets
Property and Equipment
Gross property and equipment	14,246	14,784
Leasehold improvements
Property and Equipment
Gross property and equipment	$ 3,848	$ 3,848

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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