Stockholders' Equity (Details) (USD $) Share data in Millions	3 Months Ended								12 Months Ended
	May 29, 2011	Feb. 27, 2011	Nov. 28, 2010	Aug. 29, 2010	May 30, 2010	Feb. 28, 2010	Nov. 29, 2009	Aug. 30, 2009	May 29, 2011	May 30, 2010	May 31, 2009
Comprehensive Income Schedule [Abstract]
Net earnings attributable to General Mills	$ 320,200,000	$ 392,100,000	$ 613,900,000	$ 472,100,000	$ 211,900,000	$ 332,500,000	$ 565,500,000	$ 420,600,000	$ 1,798,300,000	$ 1,530,500,000	$ 1,304,400,000
Net earnings attributable to noncontrolling interests									5,200,000	4,500,000	9,300,000
Net earnings, including earnings attributable to noncontrolling interests									1,803,500,000	1,535,000,000	1,313,700,000
Foreign Currency Transaction And Translation Adjustment Before Tax Portion Attributable To Parent									358,300,000	(163,300,000)	(286,600,000)
Net actuarial gain									93,500,000	(786,300,000)	(1,254,000,000)
Available For Sale Securities Adjustment Before Tax Period Increase Decrease									(5,800,000)	1,900,000	(600,000)
Unrealized Gain Loss On Derivatives Arising During Period Before Tax									(39,800,000)	(25,000,000)	8,000,000
Reclassification Adjustment On Derivatives Included In Net Income Before Tax									29,800,000	44,400,000	(11,900,000)
Amortization Of Defined Benefit Plan Net Prior Service Cost Credit And Net Gain Loss Recognized In Net Periodic Benefit Cost Before Tax									108,700,000	19,100,000	24,200,000
Other Comprehensive Income Loss Before Tax Portion Attributable To Parent									544,700,000	(909,200,000)	(1,520,900,000)
Other Comprehensive Income Loss Before Tax Portion Attributable To Noncontrolling Interest									700,000	200,000	(1,200,000)
Other Comprehensive Income Loss Before Tax Period Increase Decrease									545,400,000	(909,000,000)	(1,522,100,000)
Foreign Currency Translation Gain Loss Arising During Period Tax									0	0	0
Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Tax									(32,400,000)	314,800,000	477,800,000
Unrealized Holding Gain Loss On Securities Arising During Period Tax									2,200,000	(700,000)	200,000
Unrealized Gain Loss On Derivatives Arising During Period Tax									14,400,000	10,600,000	(3,400,000)
Reclassification Adjustment On Derivatives Included In Net Income Tax									(11,300,000)	(17,000,000)	4,600,000
Amortization Of Defined Benefit Plan Net Prior Service Cost And Net Gain Loss Recognized In Net Periodic Pension Cost Tax									(41,500,000)	(7,600,000)	(9,200,000)
Tax Portion Attributable To Parent									(68,600,000)	300,100,000	470,000,000
Tax Portion Attributable To Noncontrolling Interest									0	0	0
Tax									(68,600,000)	300,100,000	470,000,000
Foreign currency translation									358,300,000	(163,300,000)	(286,600,000)
Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Net Of Tax									61,100,000	(471,500,000)	(776,200,000)
Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax									(3,600,000)	1,200,000	(400,000)
Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax									(25,400,000)	(14,400,000)	4,600,000
Reclassification Adjustment On Derivatives Included In Net Income Net Of Tax									18,500,000	27,400,000	(7,300,000)
Amortization Of Defined Benefit Plan Net Prior Service Cost And Net Gain Loss Recognized In Net Periodic Pension Cost Net Of Tax									67,200,000	11,500,000	15,000,000
Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent									476,100,000	(609,100,000)	(1,050,900,000)
Other Comprehensive Income Loss Net Of Tax Portion Attributable To Noncontrolling Interest									700,000	200,000	(1,200,000)
Other comprehensive income (loss)									476,800,000	(608,900,000)	(1,052,100,000)
Comprehensive Income, Net of Tax, Including Portion Attributable to Noncontrolling Interest									2,280,300,000	926,100,000	261,600,000
AOCI Schedule [Abstract]
Foreign Currency Translation Adjustment Net Of Tax	553,200,000				194,900,000				553,200,000	194,900,000
Accumulated Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax	2,000,000				5,600,000				2,000,000	5,600,000
Accumulated Other Comprehensive Income Loss Cumulative Changes In Net Gain Loss From Cash Flow Hedges Effect Net Of Tax	(35,800,000)				(28,900,000)				(35,800,000)	(28,900,000)
Net actuarial loss	1,509,500,000				1,611,000,000				1,509,500,000	1,611,000,000
Prior service costs (credits)	20,700,000				47,500,000				20,700,000	47,500,000
Accumulated other comprehensive loss	(1,010,800,000)				(1,486,900,000)				(1,010,800,000)	(1,486,900,000)
Stockholders' Equity [Line Items]
Preferred Stock Shares Authorized	5.0								5.0
Shares purchased, shares									31.8	21.3	40.4
Treasury Stock, Value, Acquired, Cost Method									1,163,500,000	691,800,000	1,296,400,000
Actual return on assets											$ 1,100,000,000
Defined Benefit Plan Alternative Method Used To Amortize Net Gains And Losses									In fiscal 2010 and future years, the losses are reflected in pension expense using the market-related value of the plan assets over a five year period and amortized using a declining balance method over the average remaining service period of active plan participants.
Treasury Stock Acquired Repurchase Authorization										On June 28, 2010, our Board of Directors authorized the repurchase of up to 100 million shares of our common stock. Purchases under the authorization can be made in the open market or in privately negotiated transactions, including the use of call options and other derivative instruments, Rule 10b5-1 trading plans, and accelerated repurchase programs. The authorization has no specified termination date.