CONDENSED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Cash flows from operating activities:
Net earnings (loss)	$ 17,586	$ (3,120)
Adjustments to reconcile net earnings (loss) to net cash provided by operations:
Depreciation and amortization	49,964	54,890
Provision (benefit) for deferred income taxes	5,856	(533)
Amortization of share-based compensation	5,965	5,722
Amortization of major maintenance costs	7,113	8,360
Other	(3,480)	(1,138)
Increase (decrease) in cash flows resulting from changes in operating assets and liabilities, net	(50,782)	38,377
Net cash provided by operating activities	32,222	102,558
Cash flows from investing activities:
Capital expenditures	(35,075)	(14,052)
Acquisitions of businesses	(3,900)	0
Proceeds from disposition of assets	14,280	4,754
Net cash used in investing activities	(24,695)	(9,298)
Cash flows from financing activities:
Borrowings (payments) on bank credit facilities, net	1,163	(119,606)
Payments on long-term debt	(10,000)	0
Proceeds from exercise of stock options	2,336	411
Payments related to tax withholding for share-based compensation	(3,093)	(2,045)
Return of investment to noncontrolling interest and other	(348)	(25)
Net cash used in financing activities	(9,942)	(121,265)
Decrease in cash and cash equivalents	(2,415)	(28,005)
Cash and cash equivalents, beginning of year	34,813	80,338
Cash and cash equivalents, end of period	32,398	52,333
Cash paid (received) during the period:
Interest paid	18,022	18,732
Income taxes refunded, net	(24)	(117,659)
Operating cash outflow from operating leases	11,040	10,688
Non-cash investing activity:
Capital expenditures included in accounts payable	(487)	(7,207)
Right-of-use assets obtained in exchange for lease obligations	$ 6,464	$ 6,219