Consolidated Balance Sheets Parenthetical - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Consolidated Balance Sheet Parenthetical [Abstract]
Allowance for doubtful accounts receivable, current	$ 9.3	$ 4.7
Convertible preferred stock - par value (in USD per share)	$ 0.00001	$ 0.00001
Convertible preferred stock - shares authorized	10,000,000	10,000,000
Convertible preferred stock - issued	0	0
Convertible preferred stock - outstanding	0	0
Common stock - par value (in USD per share)	$ 0.00001	$ 0.00001
Common stock - shares authorized	1,000,000,000	1,000,000,000
Common stock - shares issued	384,000,000	416,200,000
Common stock - outstanding	384,000,000	416,200,000