Postretirement Health Care and Life Insurance Benefits (Estimated Postretirement Benefit Payments In Future Years) (Details) - Other Postretirement Benefits Plan [Member] $ in Millions	Feb. 03, 2018 USD ($)
Expected Benefit
2018	$ 16
2019	15
2020	14
2021	13
2022	13
2023-2027	52
Expected Federal Subsidy
2018	1
2019	0
2020	0
2021	0
2022	0
2023-2027	$ 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 benefits for defined benefit plan expected to be paid in second 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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-Publisher FASB
-Name Accounting Standards Codification
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Amount of prescription drug subsidy receipts expected in next fiscal year following latest fiscal year.

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Amount of prescription drug subsidy receipts expected in second fiscal year following latest fiscal year.

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