Fair Value Measurements (Details) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Fair value of assets and liabilities measured on recurring basis
Short-term investments	$ 26.6	$ 23.2
Forward contracts	(3.1)	3.3
Total	23.5	26.5
Fair value measurements recurring basis | Level 1
Fair value of assets and liabilities measured on recurring basis
Short-term investments	26.6	23.2
Total	26.6	23.2
Fair value measurements recurring basis | Level 2
Fair value of assets and liabilities measured on recurring basis
Forward contracts	(3.1)	3.3
Total	$ (3.1)	$ 3.3