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LONG-TERM DEBT AND FINANCE LEASE OBLIGATIONS - Senior Unsecured, Secured Notes and NALP Notes (Details) - USD ($)			12 Months Ended
	May 24, 2019	Feb. 06, 2019	Feb. 29, 2020	Feb. 23, 2019	Feb. 24, 2018	Feb. 05, 2020	Nov. 22, 2019	Aug. 15, 2019	Feb. 05, 2019	Aug. 09, 2016	May 31, 2016
Debt Instrument [Line Items]
Book value of debt				$ 10,586,400,000
ABL Facility, senior secured and unsecured notes, term loans and debentures			$ 565,300,000	698,300,000	$ 701,500,000
Gain (loss) on debt extinguishment			(111,400,000)	(8,700,000)	4,700,000
Repayments of long-term debt			5,676,600,000	3,082,300,000	870,600,000
Notes payable \| Safeway Notes Repurchase
Debt Instrument [Line Items]
Par value of note repurchased				333,700,000
Book value of debt				322,400,000
Repurchase amount of debt				333,700,000
ABL Facility, senior secured and unsecured notes, term loans and debentures				7,700,000
Gain (loss) on debt extinguishment				(11,300,000)
Notes payable \| Safeway Inc. Notes due 2020 to 2031, interest rate range of 3.95% to 7.45%
Debt Instrument [Line Items]
Par value of note repurchased	$ 34,100,000
Book value of debt	33,300,000
ABL Facility, senior secured and unsecured notes, term loans and debentures	700,000
Gain (loss) on debt extinguishment	(500,000)
Repayments of long-term debt	32,600,000
Notes payable \| NALP Notes Repurchase 2017
Debt Instrument [Line Items]
Par value of note repurchased					160,000,000.0
Book value of debt					140,200,000
Repurchase amount of debt					135,500,000
ABL Facility, senior secured and unsecured notes, term loans and debentures					3,700,000
Gain (loss) on debt extinguishment					$ 4,700,000
Notes payable \| NALP Notes Repurchase 2018
Debt Instrument [Line Items]
Par value of note repurchased				108,400,000
Book value of debt				96,400,000
Repurchase amount of debt				90,700,000
ABL Facility, senior secured and unsecured notes, term loans and debentures				1,200,000
Gain (loss) on debt extinguishment				$ 5,700,000
Notes payable \| NALP Notes Tender
Debt Instrument [Line Items]
Par value of note repurchased	402,900,000
Book value of debt	363,700,000
Repurchase amount of debt	382,700,000
ABL Facility, senior secured and unsecured notes, term loans and debentures	8,200,000
Gain (loss) on debt extinguishment	$ (19,100,000)
Notes payable \| NALP Notes Repurchase 2019
Debt Instrument [Line Items]
Par value of note repurchased			553,900,000
Book value of debt			502,000,000.0
Repurchase amount of debt			547,500,000
ABL Facility, senior secured and unsecured notes, term loans and debentures			11,300,000
Gain (loss) on debt extinguishment			$ (46,200,000)
Senior notes \| Senior Unsecured Notes, Maturity 2026
Debt Instrument [Line Items]
Repurchase amount of debt		$ 268,600,000
ABL Facility, senior secured and unsecured notes, term loans and debentures		6,400,000
Gain (loss) on debt extinguishment		(3,100,000)
Make-whole premium in debt extinguishment		$ 3,100,000
Senior notes
Debt Instrument [Line Items]
Cash						$ 18,000,000
Senior notes \| Senior Unsecured Notes, Maturity 2024
Debt Instrument [Line Items]
Face amount of debt instrument											$ 1,250,000,000.0
Stated interest rate			6.625%								6.625%
Senior notes \| Senior Unsecured Notes, Maturity 2025
Debt Instrument [Line Items]
Face amount of debt instrument										$ 1,250,000,000.0
Stated interest rate			5.75%							5.75%
Senior notes \| Senior Unsecured Notes, Maturity 2026
Debt Instrument [Line Items]
Face amount of debt instrument								$ 750,000,000.0	$ 600,000,000.0
Stated interest rate			7.50%					5.875%	7.50%
Senior notes \| Safeway Inc. 5.00% Senior Notes due 2019
Debt Instrument [Line Items]
Stated interest rate		5.00%	5.00%
Senior notes \| Senior Unsecured Notes, Maturity 2027
Debt Instrument [Line Items]
Face amount of debt instrument						600,000,000.0	$ 750,000,000.0
Stated interest rate			4.625%				4.625%
Senior notes \| Senior Unsecured Notes, Maturity 2023
Debt Instrument [Line Items]
Face amount of debt instrument						$ 750,000,000.0
Stated interest rate			3.50%			3.50%
Senior notes \| Senior Unsecured Notes, Maturity 2030
Debt Instrument [Line Items]
Face amount of debt instrument						$ 1,000,000,000.0
Stated interest rate			4.875%			4.875%
Senior notes \| Safeway Inc. 7.45% Senior Debentures due 2027
Debt Instrument [Line Items]
Stated interest rate				7.45%
Notes payable \| Safeway Inc. 7.25% Debentures due 2031
Debt Instrument [Line Items]
Stated interest rate				7.25%