Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Cash flows from operating activities:
Net income/(loss)	$ 48,106	$ (92,695)
Adjustments to reconcile net income/(loss) to net cash provided by operating activities:
Deferred income taxes	(1,603)	(28,907)
Provision for uncollectible revenue	5,606	6,840
Depreciation and amortization	167,420	165,769
Other post-employment benefits	(127,356)	38,348
Qualified pension	(2,001)	(6,447)
Stock-based compensation	5,306	3,527
Other non-cash items	3,114	1,091
Changes in assets and liabilities arising from operations:
Accounts receivable	1,415	5,141
Prepaid and other assets	(2,354)	2,694
Restricted cash	0	463
Accounts payable and accrued liabilities	(27,139)	(6,660)
Accrued interest payable	(6,557)	(6,561)
Other assets and liabilities, net	3,535	(3,567)
Total adjustments	19,386	171,731
Net cash provided by operating activities	67,492	79,036
Cash flows from investing activities:
Net capital additions	(82,921)	(91,775)
Distributions from investments and proceeds from the sale of property and equipment	230	1,101
Net cash used in investing activities	(82,691)	(90,674)
Cash flows from financing activities:
Repayments of long-term debt	(4,800)	(4,800)
Proceeds from exercise of stock options	13	32
Repayment of capital lease obligations	(568)	(1,067)
Net cash used in financing activities	(5,355)	(5,835)
Net change	(20,554)	(17,473)
Cash, beginning of period	37,587	42,700
Cash, end of period	17,033	25,227
Supplemental disclosure of cash flow information:
Capital additions included in accounts payable	7,848	7,015
Acquisition of property and equipment by capital lease	$ 1,030	$ 1,135