Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
OPERATING ACTIVITIES
Net income	$ 12,612	$ 16,775
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	48,469	23,311
Deferred income taxes	(8,659)	(1,744)
Stock-based compensation expense	152	271
Debt-related amortization	269	0
Gain on disposal of property and equipment	(6,786)	(4,258)
Changes in certain working capital items:
Trade receivables	13,649	(8,771)
Prepaid expenses and other current assets	4,864	1,083
Accounts payable, accrued liabilities, and accrued expenses	(10,978)	3,557
Accrued income taxes	12,850	7,369
Net cash provided by operating activities	66,442	37,593
INVESTING ACTIVITIES
Proceeds from sale of property and equipment	28,859	13,648
Purchases of property and equipment	(42,149)	(22,029)
Change in other assets	489	0
Net cash used in investing activities	(12,801)	(8,381)
FINANCING ACTIVITIES
Shares withheld for employee taxes related to stock-based compensation	(41)	(41)
Repayments of finance leases and debt	(47,325)	0
Net cash used in financing activities	(47,366)	(41)
Net increase in cash, cash equivalents and restricted cash	6,275	29,171
CASH, CASH EQUIVALENTS AND RESTRICTED CASH
Beginning of period	64,478	173,767
End of period	70,753	202,938
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION
Cash paid during the period for interest expense	6,121	0
Cash paid during the period for income taxes, net of refunds	232	142
Noncash investing and financing activities:
Purchased property and equipment in accounts payable	2,059	2,058
Sold revenue equipment and property in other current assets	232	1,213
Common stock dividends declared in accounts payable	1,581	1,579
RECONCILIATION OF CASH, CASH EQUIVALENTS AND RESTRICTED CASH
Cash and cash equivalents	55,506	187,085
Restricted cash included in other current assets	746	916
Restricted cash included in other assets	14,501	14,937
Total cash, cash equivalents and restricted cash	$ 70,753	$ 202,938