CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
OPERATING ACTIVITIES
Net income	$ 12,030	$ 27,467
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	35,623	30,004
Stock-based compensation expense	2,779	1,926
Gain on disposition of assets, net	(1,526)	(1,214)
Deferred income tax (benefit) provision	(2,669)	730
Other non-cash adjustments	27	135
Decrease (increase) in assets:
Accounts receivable	24,310	(4,812)
Income taxes receivable	4,243	6,000
Inventories	(2,138)	(1,488)
Prepaid expenses	2,955	2,535
Other current assets	165	121
Other non-current assets	414	(1,044)
Increase (decrease) in liabilities:
Accounts payable	7,546	19,759
Income taxes payable	2,564	1,335
Unearned revenue	(43,995)	(15,171)
Accrued payroll and related expenses	(3,358)	(10,163)
Accrued insurance expenses	(1,051)	370
Accrued state, local and other taxes	2,204	(263)
Other accrued expenses	(365)	(2,168)
Retirement plan liabilities	(1,328)	313
Long-term accrued insurance expenses	1,767	400
Other long-term liabilities	(332)	1,787
Net cash provided by operating activities	39,865	56,559
INVESTING ACTIVITIES
Capital expenditures	(32,270)	(52,778)
Proceeds from sale of assets	4,827	3,772
Net cash used for investing activities	(27,443)	(49,006)
FINANCING ACTIVITIES
Payment of dividends	(8,653)	(8,621)
Cash paid for common stock purchased and retired	(2,868)	(9,858)
Cash paid for finance lease and finance obligations	(152)	(185)
Net cash used for financing activities	(11,673)	(18,664)
Net increase (decrease) in cash and cash equivalents	749	(11,111)
Cash and cash equivalents at beginning of period	325,975	223,310
Cash and cash equivalents at end of period	326,724	212,199
Supplemental cash flows disclosure:
Income tax payments, net	193	187
Interest paid	43	42
Supplemental disclosure of noncash investing activities:
Capital expenditures included in accounts payable	$ 4,916	$ 11,054