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SIGNIFICANT ACCOUNTING POLICIES - INCOME TAXES (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
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Sep. 30, 2019 | Sep. 30, 2018 | Sep. 30, 2019 | Sep. 30, 2018
SIGNIFICANT ACCOUNTING POLICIES |  |  |  |
Tax Act, income tax expense (benefit) | $ 0.0 | $ 0.0 |  | $ (3.1)
Remeasurement and discrete adjustments related to the Tax Act |  |  | $ (2.9) |
Sequestration rate (as a percent) |  |  |  | 6.20%

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- Definition Amount of income tax expense (benefit) from effect of Tax Cuts and Jobs Act. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32639-109319 + Details
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- Definition Amount of reasonable estimate for income tax expense (benefit) for which accounting for tax effect for remeasurement of deferred tax from change in tax rate is incomplete pursuant to Tax Cuts and Jobs Act. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section S99 -Paragraph 2A -Subparagraph (SAB Topic 5.EE.Q2(b)) -URI http://asc.fasb.org/extlink&oid=116825942&loc=SL116722634-122817 + Details
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