Emergence from the Chapter 11 Cases and Fresh Start Reporting - Impact of Reorganization Adjustments (Details) - USD ($) $ in Millions		3 Months Ended	6 Months Ended
Apr. 01, 2017	Apr. 01, 2017	Jun. 30, 2016	Jun. 30, 2016
Fresh-Start Adjustment [Line Items]
Total pre-tax gain on plan effects, see also (j) below	$ 3,031.2
Successor debt issuance costs and other items, see also (f) and (g) above	50.9	$ 50.9
Net impact on accumulated deficit	5,134.3	5,134.3
Predecessor
Fresh-Start Adjustment [Line Items]
Total pre-tax gain on plan effects, see also (j) below	3,031.2	3,031.2	$ 0.0	$ 0.0
Cancellation of Predecessor Common Stock	0.2	0.2
Cancellation of Predecessor Additional paid-in capital	2,423.9	2,423.9
Cancellation of Predecessor Treasury stock	$ (371.9)	$ (371.9)

Fresh-Start Adjustment, Reorganization Gain (Loss), Net

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Amount of fresh-start adjustment to additional paid-in capital.

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Amount of fresh-start adjustment to common stock.

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Amount of increase (decrease) in debt issuance costs from fresh-start adjustment.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of fresh-start adjustment to preferred and common stock held in treasury.

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Amount of fresh-start adjustment to retained earnings or deficit.

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