Condensed Consolidated Statements of Comprehensive Income (Unaudited) (USD $)
In Millions, unless otherwise specified
3 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Statement of Comprehensive Income [Abstract]    
Net earnings including noncontrolling interest $ 294.6 $ 217.7
Other comprehensive income (loss), net of tax    
Foreign currency translation, net of tax (616.1) (238.6)
Net actuarial gain and prior service cost, net of tax 3.3 3.4
Amortization of loss on interest rate swap, net of tax 0.7 0.7
Other comprehensive income (loss) (612.1) (234.5)
Comprehensive income (loss) (317.5) (16.8)
Less: Comprehensive income (loss) attributable to noncontrolling interest (2.8) 0.7
Comprehensive income (loss) attributable to Mosaic $ (314.7) $ (17.5)