EMPLOYEE BENEFIT PLANS AND COLLECTIVE BARGAINING AGREEMENTS - Narrative (Details) employee in Thousands, $ in Millions				3 Months Ended		12 Months Ended
	Jul. 01, 2020 USD ($) union	Mar. 05, 2020 USD ($)	Jan. 30, 2015 USD ($)	Feb. 27, 2021 USD ($) employee plan	Feb. 29, 2020 USD ($) employee	Feb. 27, 2021 USD ($) employee plan	Feb. 29, 2020 USD ($) employee	Feb. 23, 2019 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Employer contributions						$ 60.0	$ 11.0	$ 199.3
Discretionary contributions								150.0
Expected employer contribution next fiscal year				$ 64.6		$ 64.6
Number of multiemployer plans | plan				27		27
Employer discretionary contribution amount in 401(k)						$ 85.8	$ 63.2	45.1
Non-cash pre-tax charge						607.2
Non-cash charge, net of tax						$ 449.4
Number of unions | union	9
Amount paid				$ 147.3
Installment period	27 months
Number of company employees | employee				300		300
Number of participants in collective bargaining agreements | employee				210	27	210	27
Number of employee scheduled to expire in collective bargaining agreements | employee				67		67
Safeway Inc
Defined Benefit Plan Disclosure [Line Items]
Multiemployer pension withdrawal liability			$ 221.8
Lump sum paid for settlement				$ 75.0
Gain recorded to reduce previously recorded estimated withdrawal liability to settlement amount					$ 43.3
Pension
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets				1,941.6	1,743.7	$ 1,941.6	$ 1,743.7	1,847.0
Payable to intermediary agent				76.1	$ 95.1	76.1	95.1
Employer contributions						58.6	9.4
Contributions by Company						524.0	469.3	451.1
Pension | Safeway Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets				1,597.0		1,597.0
Pension | Shaw's Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets				302.0		302.0
Pension | United Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets				43.0		43.0
Multiemployer Health and Welfare Plans
Defined Benefit Plan Disclosure [Line Items]
Contributions by Company						$ 1,200.0	$ 1,200.0	$ 1,300.0
Combined Plan
Defined Benefit Plan Disclosure [Line Items]
Required annual contribution		$ 23.2
Defined contribution plan, term		25 years
MAP And FELRA
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan, term						10 years
MAP And FELRA | Maximum
Defined Benefit Plan Disclosure [Line Items]
Employer discretionary contribution amount in 401(k)						$ 13.7
Variable Annuity Pension Plan (VAPP)
Defined Benefit Plan Disclosure [Line Items]
Non-cash pre-tax charge				$ 285.7		$ 4.0
Non-cash charge, net of tax	$ 213.0
Variable Annuity Pension Plan (VAPP) | Minimum
Defined Benefit Plan Disclosure [Line Items]
Transition reserve, amount paid	$ 8.0