Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Condensed Consolidated Statements of Comprehensive Income (Loss)
Net income (loss)	$ (92,719)	$ (279)	$ (98,148)	$ 1,321
Other comprehensive income (loss):
Retirement plan gain (loss)	2,485	(8,674)	22,628	(8,179)
Income tax benefit (provision) on other comprehensive income (loss)	(950)	3,315	(8,649)	3,126
Other comprehensive income (loss), net of tax	1,535	(5,359)	13,979	(5,053)
Comprehensive loss	$ (91,184)	$ (5,638)	$ (84,169)	$ (3,732)

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 5
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