New Lease Accounting Standard - Schedule of future minimum payments (Details) - USD ($) $ in Millions	Apr. 28, 2019	Jan. 28, 2019	Jan. 27, 2019
Leases [Abstract]
2020 (excluding first quarter of fiscal year 2020)	$ 77
2021	100
2022	92
2023	79
2024	57
2025 and thereafter	277
Total	682
Less imputed interest	116
Present value of net future minimum lease payments	566	$ 500
Less short-term operating lease liabilities	80		$ 0
Long-term operating lease liabilities	$ 486		$ 0

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Amount of lessee's undiscounted obligation for lease payments for operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
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Amount of lessee's undiscounted obligation for lease payments for operating lease, due after fifth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in fifth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in fourth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in second fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease having an initial or remaining lease term in excess of one year due in remainder of fiscal year following latest fiscal year.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
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Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

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