LONG-TERM DEBT - Debt Redemptions, Repurchases and Loss on Extinguishment of Debt (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jul. 01, 2018	Jun. 25, 2017	Jul. 01, 2018	Jun. 25, 2017	Dec. 31, 2017
LONG-TERM DEBT
Loss on extinguishment of debt, net	$ (19)	$ (869)	$ (5,368)	$ (869)
9.00% senior secured notes due in 2022
LONG-TERM DEBT
Face value debt reduced	95,529	15,000	95,529	15,000
Debt redeemed through tender offer	$ 500		500
Amount of debt redeemed			$ 75,000
Debt repurchased privately		$ 15,000		$ 15,000	$ 20,000

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12317-112629

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12355-112629

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration