EBP, Defined Contribution Plan Contributions Funded by Defined Benefit Surplus

No definition available.

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- Definition

EBP, Employer Contribution, Matching Percentage

+ References

No definition available.

+ Details

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- Definition

EBP, Employer Contribution Maximum Vesting Age

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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Period Type:	duration

- Definition

EBP, Employer Contribution, Participant Compensation Matched, Percentage

+ References

No definition available.

+ Details

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Data Type:	xbrli:pureItemType
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- Definition

Minimum Vesting service period for company contribution and/ or investment earning to the participant in Company Matching Contributions, Fixed Rate Contributions, Discretionary Profit-Sharing Contributions, Qualified Non-Elective Contributions, and Disability Contributions.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

EBP, Employment Termination, Benefit Payout IRS Maximum

+ References

No definition available.

+ Details

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Namespace Prefix:	mos_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

EBP, Employment Termination, Benefit Payout IRS Maximum, Age

+ References

No definition available.

+ Details

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Namespace Prefix:	mos_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Note Receivable From Participant, General Loan, Maximum Borrowing Term

+ References

No definition available.

+ Details

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Namespace Prefix:	mos_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Note Receivable From Participant, General Loan, Minimum Borrowing Term

+ References

No definition available.

+ Details

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Namespace Prefix:	mos_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Participant Contribution, Minimum Annual Contribution to Eligible Compensation, Percentage

+ References

No definition available.

+ Details

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Namespace Prefix:	mos_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Participant Loan, Basis Spread On Variable Rate

+ References

No definition available.

+ Details

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Namespace Prefix:	mos_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Requisite Service Period

+ References

No definition available.

+ Details

Name:	mos_EBPRequisiteServicePeriod
Namespace Prefix:	mos_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Secure 2.0 Act, Administrative Transition Period

+ References

No definition available.

+ Details

Name:	mos_EBPSecure2.0ActAdministrativeTransitionPeriod
Namespace Prefix:	mos_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Secure 2.0 Act, Catch-Up Contributions

+ References

No definition available.

+ Details

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Namespace Prefix:	mos_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

EBP, Secure 2.0 Act, Decrease In Excise Tax, Percent

+ References

No definition available.

+ Details

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Namespace Prefix:	mos_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

EBP, Secure 2.0 Act, Required Minimum Distribution Age

+ References

No definition available.

+ Details

Name:	mos_EBPSecure2.0ActRequiredMinimumDistributionAge
Namespace Prefix:	mos_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

EBP, Terminated Plans, Transfer Of Surplus

+ References

No definition available.

+ Details

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Namespace Prefix:	mos_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of increase in net asset available for benefit from cash contribution from employer of participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of contribution receivable from employer of participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 962
-SubTopic 325
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478873/962-325-55-17

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-05(a)(Schedule II))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 310
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478642/962-310-45-1

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of plan asset, in forfeited nonvested account, no longer allocated to participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of decrease in forfeited nonvested account of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) from employer contribution.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 962
-SubTopic 325
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478873/962-325-55-17

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (j)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-04(5)(c))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow.

+ References

+ Details

Name:	us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipantAccountMaximumBorrowingAmount
Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Percentage of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow to total participant account balance.

+ References

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of minimum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow.

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Percentage of eligible compensation contributed for participant automatically enrolled in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of maximum pretax annual compensation that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), is permitted to contribute to total pretax annual compensation.

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Interest rate on participant loan in schedule of asset held for investment of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 10
-Paragraph b
-Subparagraph (1)(i)(D)
-Publisher DOL-EBSA

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-05(a)(Schedule I))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

+ Details

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Period Type:	duration

- Details

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- Details

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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	mos_EBPPlanNameAxis=mos_MosaicInvestmentPlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	mos_EBPPlanNameAxis=mos_MosaicUnionSavingsPlanMember
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Balance Type:
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- Details

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- Details

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- Details

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- Details

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- Details

Name:	us-gaap-ebp_EmployeeBenefitPlanContributionParticipatingEmployerAxis=mos_NonElectiveContributionsMember
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- Details

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- Details

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Description of the Plan (Details)	12 Months Ended
Description of the Plan (Details)	Dec. 31, 2025 USD ($) yr	Dec. 31, 2024 USD ($)	Jan. 01, 2033 yr	Apr. 19, 2024 USD ($)	Jan. 01, 2023 yr	Dec. 31, 2022 yr
EBP, Description of Plan [Line Items]
Employment termination, benefit payout IRS maximum	$ 7,000
Employment termination, benefit payout IRS maximum age \| yr	73
EBP, Defined Contribution Plan Contributions Funded by Defined Benefit Surplus	$ 10,888
Contributions, Tranche One [Member]
EBP, Description of Plan [Line Items]
EBP, Employer Contribution, Matching Percentage	1
EBP, Employer Contribution, Participant Compensation Matched, Percentage	0.03
Contributions, Tranche Two
EBP, Description of Plan [Line Items]
EBP, Employer Contribution, Matching Percentage	0.50
EBP, Employer Contribution, Participant Compensation Matched, Percentage	0.03
EBP 004 [Member]
EBP, Description of Plan [Line Items]
Automatic, deferral rate	6.00%
Requisite service period	45 days
Minimum annual contribution to eligible compensation, percentage	1.00%
Maximum annual compensation to total compensation, percentage	75.00%
Employer	$ 23,289,295	$ 29,249,892
Employer contribution vesting service period	3 years
Employer contribution maximum vesting age \| yr	65
Decrease from employer contribution	$ 525,526	515,390
Forfeited nonvested account	682,297	439,565
Note receivable from participant, account, minimum borrowing, amount	500
Note receivable from participant, account, maximum borrowing, amount	$ 50,000
Note receivable from participant, account, maximum borrowing, to total account, percentage	50.00%
Note receivable from participant, general loan, minimum borrowing term	6 months
Note receivable from participant, general loan, maximum borrowing term	5 years
EBP, Participant Loan, Basis Spread On Variable Rate	1.00%
Secure 2.0 act, required minimum distribution age \| yr					73	72
Secure 2.0 act, decrease in excise tax, percent					25.00%	50.00%
Secure 2.0 act, catch-up contributions	$ 145,000
Secure 2.0 act, administrative transition period	2 years
Employer contributions	$ 19,614,427	19,159,045
EBP 004 [Member] \| Mosaic Investment Plan
EBP, Description of Plan [Line Items]
Terminated plans, transfer of surplus				$ 6,693,605
EBP 004 [Member] \| Mosaic Union Savings Plan
EBP, Description of Plan [Line Items]
Terminated plans, transfer of surplus				$ 12,430,982
EBP 004 [Member] \| Forecast
EBP, Description of Plan [Line Items]
Secure 2.0 act, required minimum distribution age \| yr			75
EBP 004 [Member] \| Minimum
EBP, Description of Plan [Line Items]
Asset held for investment, participant loan, interest rate	4.25%
EBP 004 [Member] \| Maximum
EBP, Description of Plan [Line Items]
Asset held for investment, participant loan, interest rate	9.50%
EBP 019 \| Non-Elective Contributions
EBP, Description of Plan [Line Items]
Employer contributions	$ 16,216,926	15,424,311
EBP 019 \| Discretionary Contributions
EBP, Description of Plan [Line Items]
Employer contributions	3,408,389	3,209,209
EBP 019 \| Safe Harbor Contributions
EBP, Description of Plan [Line Items]
Employer contributions	$ 633,556	$ 525,525