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INCOME TAXES - UNRECOGNIZED TAX BENEFITS (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Reconciliation of the beginning and ending amount of gross unrecognized tax benefits |  |  |
Balance at beginning of the period | $ 15.1 | $ 15.9 | $ 20.4
Changes in tax positions of prior years, net |  | (0.3) |
Changes in tax positions of prior years, net | 2.1 |  | 1.1
Reductions for lapse of statute of limitations | (0.8) | (0.5) | (0.1)
Revaluation of unrecognized tax benefits due to the Tax Act |  |  | (5.5)
Balance at the end | 16.4 | 15.1 | $ 15.9
Unrecognized tax benefits that, if recognized, would impact the effective rate | 13.5 |  |
Interest accrued related to unrecognized tax benefits | $ 0.1 | $ 0.4 |

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- Definition Tax Cuts and Jobs Act of 2017, Amount of decrease in unrecognized tax benefits resulting from revaluation of unrecognized benefits. + References No definition available. + Details
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
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- Definition Amount of unrecognized tax benefits. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 45 -Paragraph 10B -URI http://asc.fasb.org/extlink&oid=116821951&loc=SL37586934-109318 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=84230637&loc=SL6600010-109319 + Details
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- Definition Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=84230637&loc=SL6600010-109319 + Details
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- Definition Amount of interest expense accrued for an underpayment of income taxes. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319 + Details
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