Postretirement Health Care and Life Insurance Benefits (Estimated Postretirement Benefit Payments In Future Years) (Details) - Other Postretirement Benefits Plan [Member] $ in Millions	Feb. 02, 2019 USD ($)
Expected Benefit
2019	$ 15
2020	14
2021	13
2022	13
2023	12
2024-2028	47
Expected Federal Subsidy
2019	0
2020	0
2021	0
2022	0
2023	0
2024-2028	$ 1

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Amount of benefits for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in next fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in fifth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in fourth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in third fiscal year following latest fiscal year.

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Amount of prescription drug subsidy receipts expected after fifth fiscal year following latest fiscal year.

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