Fair Value Measurements (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2014 Senior Notes [Member]	Mar. 31, 2014 Convertible Notes payable [Member]	Mar. 18, 2013 Convertible Notes payable [Member]	Mar. 31, 2014 Recurring [Member]	Dec. 31, 2013 Recurring [Member]	Mar. 31, 2014 Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	Dec. 31, 2013 Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	Mar. 31, 2014 Recurring [Member] Significant Other Observable Inputs (Level 2) [Member]	Dec. 31, 2013 Recurring [Member] Significant Other Observable Inputs (Level 2) [Member]	Mar. 31, 2014 Recurring [Member] Significant Unobservable Inputs (Level 3) [Member]	Dec. 31, 2013 Recurring [Member] Significant Unobservable Inputs (Level 3) [Member]
Assets [Abstract]
Foreign exchange forward contracts				$ 1.6		$ 0		$ 1.6		$ 0
Liabilities [Abstract]
Interest rate swap				2.1	2.3	0	0	2.1	2.3	0	0
Notes, fair value	$ 409.2	$ 101.1
Stated percentage (in hundredths)	6.875%	8.00%	8.00%