Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
OPERATING ACTIVITIES
Net income	$ 118,095	$ 58,942
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	82,408	78,286
Deferred income taxes	2,171	(8,623)
Stock-based compensation	504	959
Amortization of Debt Issuance Costs	90	0
Gain on disposal of property and equipment	(92,806)	(27,341)
Changes in certain working capital items:
Trade receivables	(3,200)	(2,961)
Prepaid expenses and other current assets	(655)	3,041
Accounts payable, accrued liabilities, and accrued expenses	(1,725)	(9,231)
Accrued income taxes	7,668	2,622
Net cash provided by operating activities	112,550	95,694
INVESTING ACTIVITIES
Proceeds from sale of property and equipment	146,376	98,421
Purchases of property and equipment	(91,818)	(93,213)
Payments to Acquire Businesses, Net of Cash Acquired	(675,852)	0
Change in other assets	(159)	(181)
Net cash (used in) provided by investing activities	(621,453)	5,027
FINANCING ACTIVITIES
Payments of cash dividends	(3,157)	(3,198)
Proceeds from Issuance of Long-term Debt	447,343	0
Shares withheld for employee taxes related to stock-based compensation	(75)	(190)
Repayments on finance leases and debt	(29,195)	0
Repurchases of common stock	0	(31,422)
Net cash provided by (used in) financing activities	414,916	(34,810)
Net increase (decrease) in cash, cash equivalents and restricted cash	(93,987)	65,911
CASH, CASH EQUIVALENTS AND RESTRICTED CASH
Beginning of period	173,767	131,140
Ending Period	79,780	197,051
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION
Interest Paid, Excluding Capitalized Interest, Operating Activities	989	0
Cash paid during the period for income taxes, net of refunds	32,695	26,455
Noncash investing and financing activities:
Fair value of revenue equipment traded	428	0
Purchased property and equipment in accounts payable	4,430	3,258
Sold revenue equipment and property in other current assets	3,058	1,423
Common stock dividends declared in accounts payable	1,580	41,095
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability	3,985	0
Right-of-use assets obtained in exchange for operating lease liabilities through acquisitions	20,371	0
RECONCILIATION OF CASH, CASH EQUIVALENTS AND RESTRICTED CASH
Cash and Cash Equivalents, at Carrying Value	64,824	180,366
Restricted Cash and Investments, Current	880	932
Restricted Cash and Cash Equivalents, Noncurrent	14,076	15,753
Ending Period	$ 79,780	$ 197,051