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Amount of contribution received by defined benefit plan from employer which increases plan assets.

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Assumed rate, for next fiscal year, based on annual change in cost of health care cost benefits used to measure expected cost of benefits covered by defined benefit postretirement plan. Factors include, but are not limited to, estimate of health care inflation, change in health care utilization or delivery pattern, technological advances, and change in health status of participant. Excludes factors for change in composition of plan population by age and dependency status.

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Amount of accumulated benefit obligation for defined benefit plan with accumulated benefit obligation in excess of plan assets.

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Amount of plan asset for defined benefit plan with accumulated benefit obligation in excess of plan assets.

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Amount of projected benefit obligation for defined benefit pension plan with accumulated benefit obligation in excess of plan assets.

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Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

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Ultimate trend rate for health care cost for defined benefit postretirement plan.

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Year ultimate health care cost trend rate is expected to be reached, in YYYY format.

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Amount of cost for defined contribution plan.

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The shares or units in an ESOP trust that have been assigned to individual participant accounts based on a known formula. IRS rules require allocations to be nondiscriminatory generally based on compensation, length of service, or a combination of both. For any particular participant such shares or units may be vested, unvested, or partially vested.

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Amount of transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy.

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Retirement Benefits and Postemployment Benefits (Narrative) (Details) - USD ($) shares in Millions	12 Months Ended
	May 25, 2025	May 26, 2024	May 28, 2023
Defined Benefit Plan, Information About Plan Assets
Accumulated benefit obligation	$ 5,540,200,000	$ 5,684,100,000
Rate to which the cost trend rate is assumed to decline (ultimate rate)	4.50%	4.50%
Year that Rate Reaches Ultimate Trend Rate	2034	2033
Transfers into or out of level 3 investments	$ 0	$ 0
Transfer into Level 3	34,300,000
Defined Contribution Plan Disclosure [Line Items]
Net assets of money purchase plan	19,700,000	19,500,000
Recognized expense	$ 96,100,000	$ 94,000,000.0	$ 97,200,000
Under Age 65 [Member]
Defined Benefit Plan, Information About Plan Assets
Health care cost trend rate for next year	7.90%	7.30%
Over Age 65 [Member]
Defined Benefit Plan, Information About Plan Assets
Health care cost trend rate for next year	7.90%	7.30%
Defined Benefit Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	$ 30,700,000	$ 30,000,000.0
Defined Benefit Plan, Information About Plan Assets
Accumulated benefit obligation	440,100,000	438,800,000
Projected benefit obligation at end of year	5,627,500,000	5,801,700,000	5,970,700,000
Plan assets at fair value	16,300,000	12,000,000.0
Projected benefit obligation	449,700,000	449,400,000
Expected contributions next fiscal year	$ 0
Defined Benefit Pension Plans [Member] \| United States Equities [Member]
Defined Benefit Plan, Information About Plan Assets
Target Allocation, Percentage of Assets Equity Securities	8.00%
Defined Benefit Pension Plans [Member] \| International Equities [Member]
Defined Benefit Plan, Information About Plan Assets
Target Allocation, Percentage of Assets Equity Securities	5.00%
Defined Benefit Pension Plans [Member] \| Private Equities [Member]
Defined Benefit Plan, Information About Plan Assets
Target Allocation, Percentage of Assets Equity Securities	7.00%
Defined Benefit Pension Plans [Member] \| Fixed income [Member]
Defined Benefit Plan, Information About Plan Assets
Target Allocation, Percentage of Assets Equity Securities	71.00%
Defined Benefit Pension Plans [Member] \| Real asset investments [Member]
Defined Benefit Plan, Information About Plan Assets
Target Allocation, Percentage of Assets Equity Securities	9.00%
Defined Benefit Pension Plans [Member] \| United States [Member]
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	$ 0	0
Defined Benefit Plan, Information About Plan Assets
Retirement Plan Provision Termination Period	5 years
Other Postretirement Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	$ 100,000	100,000
Defined Benefit Plan, Information About Plan Assets
Accumulated benefit obligation	9,400,000	11,500,000
Projected benefit obligation at end of year	337,400,000	403,000,000.0	430,600,000
Expected contributions next fiscal year	$ 0
Other Postretirement Benefit Plans [Member] \| United States Equities [Member]
Defined Benefit Plan, Information About Plan Assets
Target Allocation, Percentage of Assets Equity Securities	26.00%
Other Postretirement Benefit Plans [Member] \| International Equities [Member]
Defined Benefit Plan, Information About Plan Assets
Target Allocation, Percentage of Assets Equity Securities	13.00%
Other Postretirement Benefit Plans [Member] \| Private Equities [Member]
Defined Benefit Plan, Information About Plan Assets
Target Allocation, Percentage of Assets Equity Securities	7.00%
Other Postretirement Benefit Plans [Member] \| Fixed income [Member]
Defined Benefit Plan, Information About Plan Assets
Target Allocation, Percentage of Assets Equity Securities	54.00%
Other Postretirement Benefit Plans [Member] \| United States [Member]
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	$ 0	0
Postemployment Benefit Plans [Member]
Defined Benefit Plan, Information About Plan Assets
Projected benefit obligation at end of year	123,100,000	$ 129,000,000.0	$ 131,000,000.0
Expected contributions next fiscal year	$ 0
General Mills Savings Plan [Member]
Defined Contribution Plan Disclosure [Line Items]
ESOP number of allocated shares	3.2	3.5
Common stock held by ESOP and company stock fund	$ 292,700,000	$ 393,000,000.0