Percentage of target incentive required payout.

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Percentage of the targeted number of performance shares maximum range and will be paid in shares of common stock.

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Percentage of the targeted number of performance shares, minimum range and will be paid in shares of common stock.

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Share based compensation arrangement by share based payment award, equity instruments other than options, outstanding, exercises in period, total intrinsic value

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Unrecognized compensation expense.

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Aggregate proceeds received by the entity during the annual period from exercises of stock or unit options and conversion of similar instruments granted under equity-based payment arrangements.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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Disclosure of the aggregate tax benefit realized from the exercise of stock options and the conversion of similar instruments during the annual period.

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Amount of cash inflow from realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Net number of share options (or share units) granted during the period.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Price of a single share of a number of saleable stocks of a company.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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SHARE-BASED PAYMENTS (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	May. 31, 2015	May. 25, 2014	May. 26, 2013	Sep. 19, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued under the plan	30,200,000
Stock option granted	4,400,000	3,600,000	3,900,000
Closing market price of our common stock	$ 38.61
Cash received from option exercises	$ 150.2	$ 104.6	$ 259.8
Actual tax benefit realized for the tax deductions from option exercises	26.7	17.4	28.7
Subsidiaries
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 1.4	$ 2.7	$ 0.8
ConAgra Foods Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued under the plan				30,000,000.0
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options vesting period	3 years
Weighted average grant date fair value, options	$ 3.36	$ 4.71	$ 2.93
Total intrinsic value of share units vested	$ 69.5	$ 46.9	$ 77.2
Compensation expense	12.4	15.3	13.5
Tax benefit related to Compensation expense	4.8	5.7	5.0
Unrecognized compensation expense	$ 11.9
Weighted average period	1 year 4 months 12 days
Stock-settled
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 21.0	26.1	26.7
Tax benefit related to Compensation expense	$ 8.1	$ 9.8	$ 9.9
Shares units granted	930,000	900,000	1,000,000
Weighted average grant date fair value	$ 31.71	$ 36.22	$ 25.59
Total intrinsic value of share units vested, other than options	$ 46.6	$ 46.4	$ 24.3
Cash-settled
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	29.2	12.4	8.0
Tax benefit related to Compensation expense	$ 11.2	$ 4.6	$ 3.0
Shares units granted	890,000	800,000	900,000
Weighted average grant date fair value	$ 30.89	$ 36.89	$ 24.74
Total intrinsic value of share units vested, other than options	$ 1.6
Share Unit Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options vesting period	3 years
Unrecognized compensation expense	$ 23.2	$ 28.2
Weighted average period	1 year 9 months 24 days	1 year 8 months 12 days
Performance period ending 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of the targeted number of performance shares, minimum range and will be paid in shares of common stock	0.00%
Percentage of the targeted number of performance shares, maximum range and will be paid in shares of common stock	220.00%
Percentage of target incentive required payout	25.00%
Performance based share plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 5.7	$ 6.5	$ 19.9
Tax benefit related to Compensation expense	2.2	2.4	7.4
Unrecognized compensation expense	$ 2.9
Weighted average period	1 year 9 months 6 days
Total intrinsic value of share units vested, other than options	$ 13.9	10.4
Restricted cash plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash flows decrease and net financing cash flow increase	$ 24.0	$ 18.9	$ 21.3
Minimum \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options expiration period	7 years
Maximum \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options expiration period	10 years