Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands		9 Months Ended
		Sep. 30, 2022	Sep. 30, 2021
Operating Activities:
Net income		$ 286,560	$ 179,474
Noncash items included in net income:
Depreciation and amortization		117,578	105,773
Deferred income taxes		824	5,086
Other, net		268	4,290
Changes in operating assets and liabilities, net		(61,156)	(26,937)
Net cash provided by operating activities		344,074	267,686
Investing Activities:
Acquisition of property and equipment		(279,057)	(154,884)
Proceeds from disposal of property and equipment		1,061	6,460
Other		0	(500)
Net cash used in investing activities		(277,996)	(148,924)
Financing Activities:
Repayments of revolving credit agreement		(1,000)	(36,410)
Borrowings of revolving credit agreement		1,000	36,410
Proceeds from stock option exercises		4,416	3,678
Shares withheld for taxes		(11,703)	(6,571)
Repayment of finance leases		(15,554)	(15,805)
Net cash used in financing activities		(22,841)	(18,698)
Net Increase in Cash, Cash Equivalents and Restricted Cash	[1]	43,237	100,064
Cash, Cash Equivalents and Restricted Cash, beginning of period	[1]	106,588	25,308
Cash, Cash Equivalents and Restricted Cash, end of period	[1]	$ 149,825	$ 125,372

[1] Cash, cash equivalents and restricted cash at the end of the period includes $3.7 million of restricted cash included in accounts receivable, net on the Condensed Consolidated Balance Sheet ending September 30, 2021.