CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (Unaudited) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Statement Of Income and Comprehensive Income [Abstract]
Net loss	$ (48,686)	$ (34,055)	$ (81,197)	$ (26,507)
Other comprehensive (loss) income:
Pension adjustment and reclassification adjustment, net of taxes	127	125	254	250
Foreign currency translation	164	153	856	(876)
Unrealized loss on securities, net of taxes		(22)	(9)	(2)
Comprehensive loss	$ (48,395)	$ (33,799)	$ (80,096)	$ (27,135)

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
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Other Comprehensive Income
-URI http://asc.fasb.org/extlink&oid=51831270

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Comprehensive Income
-URI http://asc.fasb.org/extlink&oid=51831223

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
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-URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e557-108580

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=51831255

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Reference 6: http://www.xbrl.org/2003/role/presentationRef
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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature, attributable to parent entity.

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Amount after tax and reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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