Postretirement Health Care and Life Insurance Benefits (Narrative) (Details) $ in Millions	12 Months Ended
Jan. 30, 2021 USD ($)
Expected Federal Subsidy [Abstract]
Estimated amount for entire time period presented	$ 1
Maximum [Member]
Expected Federal Subsidy [Abstract]
2021	1
2022	1
2023	1
2024	1
2025	1
2026-2030	$ 1

Expected Federal Subsidy [Abstract]

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- Definition

Amount of receipt from prescription drug subsidy which increases plan assets of defined benefit postretirement plan.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)(5)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 60
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39716-114964

+ Details

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- Definition

Amount of prescription drug subsidy receipt expected after fifth fiscal year following current fiscal year.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 60
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39716-114964

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- Definition

Amount of prescription drug subsidy receipt expected in next fiscal year following current fiscal year.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 60
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39716-114964

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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- Definition

Amount of prescription drug subsidy receipt expected in fifth fiscal year following current fiscal year.

+ References

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- Definition

Amount of prescription drug subsidy receipt expected in fourth fiscal year following current fiscal year.

+ References

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- Definition

Amount of prescription drug subsidy receipt expected in third fiscal year following current fiscal year.

+ References

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- Definition

Amount of prescription drug subsidy receipt expected in second fiscal year following current fiscal year.

+ References

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