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RECEIVED SETTLEMENTS AND COMMITMENTS AND CONTINGENCIES (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2017 USD ($) Claim | Dec. 31, 2016 USD ($) Claim | Dec. 31, 2015 USD ($)
Received settlements [Abstract] |  |  |
Settlement amount | $ | $ 0 | $ 5,328 | $ 0
Commitments and Contingencies [Abstract] |  |  |
Number of claims filed | Claim | 0 | 0 |

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- Definition Amount of gain (loss) recognized in settlement of litigation and insurance claims. Excludes claims within an insurance entity's normal claims settlement process. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349 + Details
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- Definition Number of pending claims pertaining to a loss contingency. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14435-108349 + Details
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