Postretirement Medical Benefits - Additional Information (Details) $ in Millions	12 Months Ended
Feb. 01, 2020 USD ($)
Retirement Benefits [Abstract]
Minimum retirement age for participation in plan	55 years
Minimum service period for participation in plan	10 years
Expected contributions in 2020	$ 0.7
Expected amortization of net actuarial gain in 2020	$ 0.8

Defined Benefit Plan, Minimum Retirement Age For Participation

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- Definition

Defined Benefit Plan, Minimum Service Period At Retirement For Eligibility

+ References

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Amount included in accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan expected to be recognized in net periodic benefit (cost) credit for fiscal year following most recent annual statement of financial position.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (s)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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- Definition

Amount of contributions expected to be received by defined benefit plan from employer in next fiscal year following latest fiscal year.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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