v3.26.1
Document and Entity Information
Aug. 11, 2026
Document And Entity Information [Line Items]  
Entity Registrant Name ILLINOIS TOOL WORKS INC
Amendment Flag false
Entity Central Index Key 0000049826
Document Type 8-K
Document Period End Date Aug. 11, 2026
Entity Incorporation State Country Code DE
Entity File Number 1-4797
Entity Tax Identification Number 36-1258310
Entity Address, Address Line One 155 Harlem Avenue
Entity Address, City or Town Glenview
Entity Address, State or Province IL
Entity Address, Postal Zip Code 60025
City Area Code 847
Local Phone Number 724-7500
Written Communications false
Soliciting Material false
Pre Commencement Tender Offer false
Pre Commencement Issuer Tender Offer false
Entity Emerging Growth Company false
Common Stock [Member]  
Document And Entity Information [Line Items]  
Security 12b Title Common Stock
Trading Symbol ITW
Security Exchange Name NYSE
A 0.625 Euro Notesdue 2027 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title 0.625% Euro Notes due 2027
Trading Symbol ITW27
Security Exchange Name NYSE
A 3.250 Euro Notes Due 2028 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title 3.250% Euro Notes due 2028
Trading Symbol ITW28
Security Exchange Name NYSE
A 2.125 Euro Notesdue 2030 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title 2.125% Euro Notes due 2030
Trading Symbol ITW30
Security Exchange Name NYSE
A 1.00 Euro Notesdue 2031 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title 1.00% Euro Notes due 2031
Trading Symbol ITW31
Security Exchange Name NYSE
A 3.375 Euro Notes Due 2032 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title 3.375% Euro Notes due 2032
Trading Symbol ITW32
Security Exchange Name NYSE
A 3.00 Euro Notesdue 2034 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title 3.00% Euro Notes due 2034
Trading Symbol ITW34
Security Exchange Name NYSE