COMMITMENTS AND CONTINGENCIES - Undiscounted Cash Flows Owed (Details) $ in Thousands	Dec. 31, 2019 USD ($)
COMMITMENTS AND CONTINGENCIES
2020	$ 4,583
2021	4,469
2022	4,459
2023	3,920
2024	3,660
Thereafter	39,831
Total lease payments	60,922
Less imputed interest	(23,316)
Present value of operating lease liabilities	37,606
Contractual commitments for supply of services, labor and materials	$ 21,000

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Amount of lessee's undiscounted obligation for lease payments for operating lease.

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