Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Purchase of common stock	$ (1,463)	$ (3,079)
Withholding taxes paid for conversion of employee stock awards	(1,436)	(1,231)
OPERATING ACTIVITIES:
Net earnings from continuing operations	9,796	8,171
Net earnings from discontinued operations	(192)	(47)
Adjustments to reconcile net earnings to net cash provided by operating activities:
Depreciation and amortization	39,033	32,534
Pension and post-retirement	1,995	3,382
Deferred income taxes	6,149	3,831
Amortization of stock-based compensation	784	654
Net (gain) loss on financial instruments	(209)	121
Changes in assets and liabilities:
Accounts receivable	(6,487)	219
Inventory and prepaid supplies	(4,413)	1,341
Accounts payable	6,932	(1,995)
Unearned revenue	4,765	(2,719)
Accrued expenses, salaries, wages, benefits and other liabilities	(9,911)	(920)
Pension and post-retirement assets	(3,039)	(2,196)
Other	283	1,432
NET CASH PROVIDED BY OPERATING ACTIVITIES	44,210	44,309
INVESTING ACTIVITIES:
Capital expenditures	(83,786)	(71,673)
Investment in nonconsolidated affiliate	(640)	0
NET CASH (USED IN) INVESTING ACTIVITIES	(79,701)	(71,673)
FINANCING ACTIVITIES:
Principal payments on long term obligations	(10,337)	(6,189)
Proceeds from borrowings	60,000	60,000
NET CASH PROVIDED BY FINANCING ACTIVITIES	46,764	49,501
NET INCREASE IN CASH AND CASH EQUIVALENTS	11,273	22,137
CASH AND CASH EQUIVALENTS AT BEGINNING OF YEAR	16,358	17,697
CASH AND CASH EQUIVALENTS AT END OF PERIOD	27,631	39,834
SUPPLEMENTAL CASH FLOW INFORMATION:
Interest paid, net of amount capitalized	3,406	2,587
Federal alternative minimum and state income taxes paid	113	0
SUPPLEMENTAL NON-CASH INFORMATION:
Accrued capital expenditures	18,251	7,084
Net (gain) loss on financial instruments	1,869	(528)
Redemption of long term deposits	$ 4,725	$ 0