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Derivatives and Fair Value Measurements Fair Value of Long-term Debt (Details) - Successor - USD ($) $ in Millions | Dec. 31, 2018 | Dec. 31, 2017
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Carrying Amount |  |
Fair Value of Debt [Line Items] |  |
Current and Long-term debt | $ 1,367.0 | $ 1,460.8
Estimated Fair Value |  |
Fair Value of Debt [Line Items] |  |
Current and Long-term debt | $ 1,366.2 | $ 1,547.4

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- Definition Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13433-108611 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13476-108611 + Details
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