Accounts Receivable, Notes Receivable, Allowance for Doubtful Accounts and Bad Debt - Components of Total Notes Receivable, Net (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total accounts and notes receivable, net	$ 744.6	$ 577.3
Notes Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Notes receivable	282.1	236.9
Notes receivable allowance for doubtful accounts	(5.9)	(5.6)
Total accounts and notes receivable, net	276.2	231.3
Notes receivable, balances over 90 days past due	19.9	9.1
Notes receivable allowance for doubtful accounts, balances over 90 days past due	(3.5)	(3.3)
Notes receivable, net, balances over 90 days past due	16.4	5.8
Financing receivable, percentage greater than 90 days past due	5.90%	2.50%
United States | Notes Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Notes receivable	95.3	65.1
Notes receivable allowance for doubtful accounts	0	0
Notes receivable, balances over 90 days past due	7.9	0.4
Notes receivable allowance for doubtful accounts, balances over 90 days past due	0	0
International | Notes Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Notes receivable	186.8	171.8
Notes receivable allowance for doubtful accounts	(5.9)	(5.6)
Notes receivable, balances over 90 days past due	12.0	8.7
Notes receivable allowance for doubtful accounts, balances over 90 days past due	$ (3.5)	$ (3.3)