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LEASES - Maturities of lease liabilities (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023 | Dec. 31, 2023
Lessor, Lease, Description [Line Items] |  |  |  |  |
2024 (excluding the nine months ended September 30, 2024) | $ 4,957 |  | $ 4,957 |  |
Year 1 | 18,858 |  | 18,858 |  | $ 18,048
Year 2 | 15,023 |  | 15,023 |  | 16,022
Year 3 | 12,143 |  | 12,143 |  | 11,755
Year 4 | 9,273 |  | 9,273 |  | 9,327
Year 5 |  |  |  |  | 7,807
Thereafter | 84,025 |  | 84,025 |  |
Thereafter |  |  |  |  | 80,637
Total lease payments | 144,279 |  | 144,279 |  | 143,596
Less imputed interest | (56,694) |  | (56,694) |  | (57,133)
Total | $ 87,585 |  | $ 87,585 |  | $ 86,463
Operating Lease, Liability, Statement of Financial Position [Extensible Enumeration] | Lease Liability, Current, Lease Liability, Noncurrent |  | Lease Liability, Current, Lease Liability, Noncurrent |  | Lease Liability, Current, Lease Liability, Noncurrent
Finance Lease, Liability, to be Paid, Fiscal Year Maturity [Abstract] |  |  |  |  |
2024 (excluding the nine months ended September 30, 2024) | $ 543 |  | $ 543 |  |
Year 1 | 1,541 |  | 1,541 |  | $ 2,030
Year 2 | 721 |  | 721 |  | 1,488
Year 3 | 685 |  | 685 |  | 601
Year 4 | 554 |  | 554 |  | 534
Year 5 |  |  |  |  | 505
Thereafter |  |  |  |  | 2,145
Thereafter | 2,145 |  | 2,145 |  |
Total lease payments | 6,189 |  | 6,189 |  | 7,303
Less imputed interest | (1,431) |  | (1,431) |  | (1,662)
Total | $ 4,758 |  | $ 4,758 |  | $ 5,641
Finance Lease, Liability, Statement of Financial Position [Extensible Enumeration] | Lease Liability, Current, Lease Liability, Noncurrent |  | Lease Liability, Current, Lease Liability, Noncurrent |  | Lease Liability, Current, Lease Liability, Noncurrent
Lease income | $ 2,075 | $ 1,948 | $ 6,293 | $ 5,810 |
Maturities of future undiscounted lease payments |  |  |  |  |
2024 (excluding the nine months ended September 30, 2024) | 1,837 |  | 1,837 |  |
2025 | 7,178 |  | 7,178 |  |
2026 | 6,848 |  | 6,848 |  |
2027 | 5,624 |  | 5,624 |  |
2028 | 5,228 |  | 5,228 |  |
Thereafter | 13,568 |  | 13,568 |  |
Total future lease payments | 40,283 |  | 40,283 |  |
Network asset |  |  |  |  |
Finance Lease, Liability, to be Paid, Fiscal Year Maturity [Abstract] |  |  |  |  |
Lease income | $ 2,100 | $ 1,900 | $ 6,300 | $ 5,800 |

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