Investments in Non-Consolidated Companies (Details 2) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Equity Method Investment, Summarized Financial Information, Income Statement
Net sales	$ 4,058.5	$ 3,555.6	$ 2,871.2
Net earnings (loss)	(215.0)	(5.4)	95.3
Equity in net (loss) earnings of nonconsolidated companies	(59.4)	(4.5)	16.7
Equity Method Investment Summarized Financial Information Balance Sheet
Total assets	9,682.5	9,042.9	8,623.6
Total liabilities	7,512.7	6,658.2	5,971.9
Mosaic's share of equity in net assets	$ 554.7	$ 609.1	$ 712.8

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