Investments - Summary (Details) - USD ($) $ in Millions	Jul. 31, 2020	Jan. 31, 2020	Aug. 02, 2019
Short-term investments:
Available-for-sale debt securities	$ 435	$ 160	$ 275
Held-to-maturity securities	650	0	0
Total short-term investments	1,085	160	275
Long-term investments:
Available-for-sale debt securities	326	372	179
Total long-term investments	$ 326	$ 372	$ 179

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121558606&loc=SL82898722-210454

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-Topic 320
-SubTopic 10
-Section 45
-Paragraph 2
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