Leases - Narrative (Details)	3 Months Ended		12 Months Ended
	Sep. 30, 2019 USD ($) store	Mar. 31, 2019 USD ($) store	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($) store
Operating Leased Assets [Line Items]
Proceeds from sale-leaseback transactions			$ 5,000,000
Store rationalization charges			$ 231,000,000	$ 0	$ 215,000,000
Proceeds from sale-leaseback transactions				0	265,000,000
Long-term portion of lease obligations associated with facility closings				$ 269,000,000
Retail/ LTC
Operating Leased Assets [Line Items]
Number of under performing stores | store	22	46
Store rationalization charges	$ 96,000,000	$ 135,000,000			$ 215,000,000
Number of stores closed | store					71
Distribution centers and Corporate Offices | Minimum
Operating Leased Assets [Line Items]
Lease term			15 years
Distribution centers and Corporate Offices | Maximum
Operating Leased Assets [Line Items]
Lease term			25 years
Equipment | Minimum
Operating Leased Assets [Line Items]
Lease term			3 years
Equipment | Maximum
Operating Leased Assets [Line Items]
Lease term			10 years