Consolidated Statements of Cash Flows - USD ($)	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Write off of Deferred Debt Issuance Cost	$ 0	$ 6,505,000
Withholding taxes paid for conversion of employee stock awards	1,519,000	1,242,000
OPERATING ACTIVITIES:
Net earnings from continuing operations	154,194,000	184,522,000
Net earnings from discontinued operations	1,736,000	2,374,000
Adjustments to reconcile net earnings to net cash provided by operating activities:
Depreciation and amortization	265,306,000	249,574,000
Pension and post-retirement	1,662,000	5,433,000
Deferred income taxes	40,892,000	55,023,000
Amortization of stock-based compensation	6,149,000	5,524,000
Proceeds from Contributions from Affiliates	5,577,000	1,364,000
Net (gain) loss on financial instruments	(4,700,000)	(4,800,000)
Changes in assets and liabilities:
Accounts receivable	(45,149,000)	(38,235,000)
Inventory and prepaid supplies	(9,200,000)	4,561,000
Accounts payable	4,863,000	18,261,000
Unearned revenue	(10,685,000)	(11,545,000)
Accrued expenses, salaries, wages, benefits and other liabilities	12,789,000	7,181,000
Pension and post-retirement balances	(18,737,000)	(20,743,000)
Other	(1,925,000)	(2,764,000)
NET CASH PROVIDED BY OPERATING ACTIVITIES	398,070,000	429,238,000
INVESTING ACTIVITIES:
Expenditures for property and equipment	(448,358,000)	(428,126,000)
Proceeds from property and equipment	3,759,000	3,524,000
Investment in nonconsolidated affiliate	(16,233,000)	(2,155,000)
NET CASH (USED IN) INVESTING ACTIVITIES	(460,832,000)	(426,757,000)
FINANCING ACTIVITIES:
Payment for Debt Extinguishment or Debt Prepayment Cost	(115,204,000)	0
Repayment of Long-term Debt, Long-term Lease Obligation, and Capital Security	345,525,000	1,758,018,000
Proceeds from revolving credit facilities	510,000,000	1,430,600,000
Payments for financing costs	0	(3,099,000)
Proceeds from Issuance of Unsecured Debt	0	207,400,000
NET CASH PROVIDED BY FINANCING ACTIVITIES	47,752,000	7,608,000
Proceeds from issuance of warrants	0	131,967,000
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	(15,010,000)	10,089,000
CASH AND CASH EQUIVALENTS AT BEGINNING OF YEAR	69,496,000	39,719,000
CASH AND CASH EQUIVALENTS AT END OF YEAR	54,486,000	49,808,000
SUPPLEMENTAL CASH FLOW INFORMATION:
Interest paid, net of amount capitalized	39,711,000	39,104,000
Federal and state income taxes paid	1,735,000	1,859,000
SUPPLEMENTAL NON-CASH INFORMATION:
Accrued expenditures for property and equipment	51,085	27,358,000
Net (gain) loss on financial instruments	$ 9,402,000	$ 37,797,000