Debt, Factoring and Customer Financing Arrangements - Accounts Receivable Factoring Arrangements (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Debt Disclosure [Abstract]
Factoring agreement, capacity of trade receivables to sell	$ 236,000,000	$ 151,000,000
Factoring agreements utilized	124,000,000	73,900,000
Factoring agreements current capacity	71,100,000	65,300,000
Factoring agreements utilized	34,600,000	$ 38,300,000
Overdraft facility capacity	$ 18,000,000