Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Write off of Deferred Debt Issuance Cost	$ 2,764	$ 3,816
Withholding taxes paid for conversion of employee stock awards	1,115	1,384
OPERATING ACTIVITIES:
Net earnings from continuing operations	133,733	22,634
Net earnings from discontinued operations	3,772	31
Adjustments to reconcile net earnings to net cash provided by operating activities:
Depreciation and amortization	77,001	69,579
Pension and post-retirement	972	3,925
Deferred income taxes	7,947	4,705
Amortization of stock-based compensation	1,821	1,474
Net gain on financial instruments	10,900	3,800
Changes in assets and liabilities:
Accounts receivable	(4,123)	15,754
Inventory and prepaid supplies	(4,543)	(4,441)
Accounts payable	6,169	2,206
Unearned revenue	3,604	3,080
Accrued expenses, salaries, wages, benefits and other liabilities	(17,742)	(9,267)
Pension and post-retirement assets	(5,483)	(2,252)
Other	186	658
NET CASH PROVIDED BY OPERATING ACTIVITIES	99,034	107,402
INVESTING ACTIVITIES:
Expenditures for property and equipment	(143,495)	(91,856)
Proceeds from property and equipment	32	0
Investment in nonconsolidated affiliate	(3,049)	(15,844)
NET CASH USED IN INVESTING ACTIVITIES	(146,512)	(107,700)
FINANCING ACTIVITIES:
Principal payments on long term obligations	(499,064)	(7,969)
Proceeds from borrowings	80,000	0
Proceeds from bond issuance	500,000	0
Proceeds from convertible notes	0	(264)
Payments for financing costs	(7,481)	0
NET CASH PROVIDED BY (USED IN) FINANCING ACTIVITIES	72,340	(9,617)
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	24,862	(9,915)
CASH AND CASH EQUIVALENTS AT BEGINNING OF YEAR	46,201	59,322
CASH AND CASH EQUIVALENTS AT END OF YEAR	71,063	49,407
SUPPLEMENTAL CASH FLOW INFORMATION:
Interest paid, net of amount capitalized	8,864	16,925
Federal alternative minimum and state income taxes paid	48	0
SUPPLEMENTAL NON-CASH INFORMATION:
Accrued expenditures for property and equipment	27,914	15,812
Net (gain) loss on financial instruments	$ 107,044	$ 4,500