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Derivatives and Fair Value Measurements Pre-Tax Gains and Losses on Hedging Derivatives (Details) - Designated as Hedging Instrument [Member] - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Apr. 01, 2017 | Mar. 31, 2016 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Predecessor |  |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |  |  |
Derivative, Gain (Loss) on Derivative, Net |  | $ (27.6) |  |  | $ (316.1) |  |  |
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net |  |  |  |  |  |  | $ (199.0) |
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net |  | (27.6) |  |  |  |  | (438.4) | [1]
loss reclassified from Accumulated OCI into income | [2] |  |  |  | (231.7) |  |  |
loss recognized in income on derivatives |  |  |  |  | (84.4) |  |  |
Derivative Instruments, Gain (Loss) Recognized in Income, Ineffective Portion and Amount Excluded from Effectiveness Testing, Net |  |  |  |  |  |  | 1.6 |
Predecessor | Foreign Exchange Contract [Member] |  |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net |  |  | $ 13.6 |  |  |  |  |
Predecessor | Diesel Fuel Hedge Contracts [Member] |  |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net |  |  | $ 9.0 |  |  |  |  |
Predecessor | Operating Costs and Expenses [Member] | Commodity Contract [Member] |  |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |  |  |
Derivative, Gain (Loss) on Derivative, Net |  | (11.0) |  |  | (98.0) |  | (77.0) |
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net |  | (11.0) |  |  |  |  |  |
loss reclassified from Accumulated OCI into income |  |  |  |  | (86.1) | [2] | (122.0) | [1]
loss recognized in income on derivatives |  |  |  |  | (11.9) |  | 1.6 |
Predecessor | Operating Costs and Expenses [Member] | Foreign Exchange Contract [Member] |  |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |  |  |
Derivative, Gain (Loss) on Derivative, Net |  | (16.6) |  |  | (142.9) |  | (122.0) |
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net |  | $ (16.6) |  |  |  |  |  |
loss reclassified from Accumulated OCI into income |  |  |  |  | (145.6) | [2] | (316.4) | [1]
loss recognized in income on derivatives |  |  |  |  | 2.7 |  | $ 0.0 |
Predecessor | Reorganization items [Member] | Commodity Contract [Member] |  |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |  |  |
Derivative, Gain (Loss) on Derivative, Net |  |  |  |  | (38.8) |  |  |
loss reclassified from Accumulated OCI into income | [2] |  |  |  | 0.0 |  |  |
loss recognized in income on derivatives |  |  |  |  | (38.8) |  |  |
Predecessor | Reorganization items [Member] | Foreign Exchange Contract [Member] |  |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |  |  |
Derivative, Gain (Loss) on Derivative, Net |  |  |  |  | (36.4) |  |  |
loss reclassified from Accumulated OCI into income | [2] |  |  |  | 0.0 |  |  |
loss recognized in income on derivatives |  |  |  |  | $ (36.4) |  |  |
Successor |  |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |  |  |
Derivative, Gain (Loss) on Derivative, Net |  |  |  | $ 1.8 |  |  |  |
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net |  |  |  | 3.3 |  |  |  |
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net |  |  |  | (1.5) |  |  |  |
Successor | Operating Costs and Expenses [Member] | Foreign Exchange Contract [Member] |  |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |  |  |
Derivative, Gain (Loss) on Derivative, Net |  |  |  | 1.8 |  |  |  |
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net |  |  |  | 3.3 |  |  |  |
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net |  |  |  | $ (1.5) |  |  |  |
[1] | Includes the reclassification from "Accumulated other comprehensive loss" into earnings of $14.9 million of previously unrecognized gains on foreign currency cash flow hedge contracts monetized in the fourth quarter of 2012.
[2] | (1) Includes the reclassification from "Accumulated other comprehensive loss" into earnings of $13.6 million and $9.0 million of previously unrecognized losses on foreign currency and fuel contracts, respectively, monetized in the first quarter of 2016.

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- Definition Amount of increase (decrease) in the fair value of derivatives recognized in the income statement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5618551-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (a),(c),(d),(e) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959 + Details
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- Definition The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4D -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624177-113959 + Details
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- Definition The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 25 -Section 50 -Paragraph 1 -Subparagraph (a)(1),(2) -URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986 + Details
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- Definition The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959 + Details
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