Note 6 - Accrued Liabilities and Other Long-Term Liabilities	12 Months Ended
Dec. 31, 2023
Notes To Financial Statements
ACCRUED LIABILITIES AND OTHER LONG-TERM LIABILITIES	NOTE 6—ACCRUED LIABILITIES AND OTHER LONG-TERM LIABILITIES Accrued liabilities at December 31, 2023 consisted of accrued compensation of $14.6 million and various other liabilities. Accrued expenses at December 31, 2022 consisted of accrued compensation of $12.1 million and various other liabilities. The Company sponsors a defined contribution plan to assist eligible employees in providing for their future retirement needs. Contribution expenses related to the plan totaled $3.1 million, $2.3 million, and $1.2 million for the years ended December 31, 2023, 2022, and 2021, respectively. Other long-term liabilities were comprised primarily of worker’s compensation and occupational disease obligations discussed below. Workers’ Compensation and Occupational Disease Obligations We are self-insured for certain losses relating to workers’ compensation claims and occupational disease obligations under the Federal Mine Safety and Health Act of 1969, as amended. Starting in 2023, the Company also elected to self-insure employee medical expenses. We purchase insurance coverage to reduce our exposure to significant levels of these claims. Self-insured losses are accrued based upon estimates of the aggregate liability for uninsured claims incurred as of the balance sheet date using claims data and actuarial assumptions. The occupational disease benefit obligation represents the present value of the actuarially computed liabilities for such benefits over the employees’ applicable years of service. The occupational disease benefit liability was calculated using a discount rate of 5.3% and 5.6% at December 31, 2023 and 2022, respectively. As of December 31, 2023, the estimated aggregate liability for uninsured claims totaled $5.2 million, including $2.3 million of occupational disease obligations. Of the aggregate liability, $3.1 million was included in Other long-term liabilities on the Consolidated Balance Sheet. As of December 31, 2022, the estimated aggregate liability for uninsured claims totaled $3.6 million, including $1.5 million of occupational disease obligations. Of the aggregate liability, $2.7 million was included in Other long-term liabilities within the Consolidated Balance Sheet.

Note 6 - Accrued Liabilities and Other Long-Term Liabilities

12 Months Ended

Dec. 31, 2023

ACCRUED LIABILITIES AND OTHER LONG-TERM LIABILITIES

NOTE 6—ACCRUED LIABILITIES AND OTHER LONG-TERM LIABILITIES

Accrued liabilities at December 31, 2023 consisted of accrued compensation of $14.6 million and various other liabilities. Accrued expenses at December 31, 2022 consisted of accrued compensation of $12.1 million and various other liabilities. The Company sponsors a defined contribution plan to assist eligible employees in providing for their future retirement needs. Contribution expenses related to the plan totaled $3.1 million, $2.3 million, and $1.2 million for the years ended December 31, 2023, 2022, and 2021, respectively.

Other long-term liabilities were comprised primarily of worker’s compensation and occupational disease obligations discussed below.

Workers’ Compensation and Occupational Disease Obligations

We are self-insured for certain losses relating to workers’ compensation claims and occupational disease obligations under the Federal Mine Safety and Health Act of 1969, as amended. Starting in 2023, the Company also elected to self-insure employee medical expenses. We purchase insurance coverage to reduce our exposure to significant levels of these claims. Self-insured losses are accrued based upon estimates of the aggregate liability for uninsured claims incurred as of the balance sheet date using claims data and actuarial assumptions. The occupational disease benefit obligation represents the present value of the actuarially computed liabilities for such benefits over the employees’ applicable years of service. The occupational disease benefit liability was calculated using a discount rate of 5.3% and 5.6% at December 31, 2023 and 2022, respectively.

As of December 31, 2023, the estimated aggregate liability for uninsured claims totaled $5.2 million, including $2.3 million of occupational disease obligations. Of the aggregate liability, $3.1 million was included in Other long-term liabilities on the Consolidated Balance Sheet. As of December 31, 2022, the estimated aggregate liability for uninsured claims totaled $3.6 million, including $1.5 million of occupational disease obligations. Of the aggregate liability, $2.7 million was included in Other long-term liabilities within the Consolidated Balance Sheet.