Related Party Transactions (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Related Party Transaction [Line Items]
Indemnification asset	$ 24.1		$ 40.6
Transactions with non-consolidated companies included in net sales	148.6	$ 262.5
Transactions with non-consolidated companies included in cost of sales	177.1	251.0
Investee
Related Party Transaction [Line Items]
Net amount due to our non-consolidated companies	133.7
Net amount due from our non-consolidated companies			23.2
Indemnification asset	$ 24.1
Beneficial Owner
Related Party Transaction [Line Items]
Mosaic's ownership percentage	50.00%
Bridge loans to affiliate	$ 74.7		74.7
Allowance against bridge loans to affiliates	54.2		$ 54.2
Equity Method Investee
Related Party Transaction [Line Items]
Transactions with non-consolidated companies included in net sales	$ 2.4	$ 2.7
Percent of joint venture production Mosaic expects to market	25.00%

Percent of joint venture production Mosaic expects to market

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Amount of allowance for credit loss of accounts and financing receivables. Includes, but is not limited to, notes and loan receivable.

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Amount of payable due to an entity that is affiliated with the reporting entity by means of direct or indirect ownership.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Amounts due from parties associated with the reporting entity as evidenced by a written promise to pay, due within 1 year (or 1 business cycle).

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