Accounts Receivable Factoring and Other Receivables (Details) - USD ($) $ in Millions	3 Months Ended				6 Months Ended	12 Months Ended
	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Jun. 30, 2016	Jun. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accounts, Notes, Loans and Financing Receivable [Line Items]
Transfer Of Accounts Receivable, Accounted For As Sale Of AR						$ 227.0
Accounts receivable sold, carrying value			$ 156.0				$ 156.0
Proceeds from Sale of Accounts Receivable						223.0	154.0
Gain (loss) on sale of accounts receivable						$ (1.0)	(0.7)
Receivable with Imputed Interest, Face Amount		$ 65.0		$ 120.0	$ 120.0
Trade Receivables Held-for-sale, Reconciliation to Cash Flow, Deductions from Held-for-sale		$ 65.0		120.0
Receivable With Imputed Interest, Term		3 years			3 years
Receivable with Imputed Interest, Effective Yield (Interest Rate)		4.625%			6.50%
Notes Receivable, Fair Value Disclosure		$ 58.0
Financing Receivable, Allowance for Credit Losses, Write-downs				$ 84.0			$ 76.0
Proceeds from Sale of Notes Receivable	$ 59.0		44.0
Gain (Loss) on Sale of Notes Receivable			$ 8.0
MEXICO
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable sold, carrying value								$ 78.0
Proceeds from Sale of Accounts Receivable								77.0
Gain (loss) on sale of accounts receivable								$ (0.2)