v3.19.3.a.u2
Document and Entity Information
Jan. 23, 2020
Cover [Abstract]  
Entity Registrant Name COSTCO WHOLESALE CORP /NEW
Security 12b Title Common Stock, $.01 Par Value
Security Exchange Name NASDAQ
Amendment Flag false
Entity Central Index Key 0000909832
Document Type 8-K
Document Period End Date Jan. 23, 2020
Entity Incorporation State Country Code WA
Entity File Number 0-20355
Entity Tax Identification Number 91-1223280
Entity Address, Address Line One 999 Lake Drive
Entity Address, City or Town Issaquah
Entity Address, State or Province WA
Entity Address, Postal Zip Code 98027
City Area Code 425
Local Phone Number 313-8100
Written Communications false
Soliciting Material false
Pre Commencement Tender Offer false
Pre Commencement Issuer Tender Offer false
Trading Symbol COST
Entity Emerging Growth Company false