Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Condensed Consolidated Statements of Comprehensive Income (Loss)
Net loss	$ (5,736)	$ (1,952)
Other comprehensive income (loss):
Retirement plan gain (loss)	(120)	21,142
Income tax benefit (provision) on other comprehensive income (loss)	31	(8,080)
Other comprehensive income (loss), net of tax	(89)	13,062
Comprehensive income (loss)	$ (5,825)	$ 11,110

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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Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

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Amount of tax expense (benefit) allocated to other comprehensive income (loss) attributable to parent entity.

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