Statement of Income (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Income Statement [Abstract]
Operating Revenue	$ 4,031	$ 4,011	$ 12,124	$ 11,961
Cost of revenue	2,319	2,371	7,004	7,120
Selling, administrative, and research and development expenses	615	624	1,980	1,935
Amortization and impairment of intangible assets	27	33	88	102
Operating Income	1,070	983	3,052	2,804
Interest expense	(67)	(52)	(196)	(147)
Other income (expense)	10	26	40	64
Income Before Taxes	1,013	957	2,896	2,721
Income Taxes	241	230	656	594
Net Income	$ 772	$ 727	$ 2,240	$ 2,127
Net Income Per Share:
Basic (in dollars per share)	$ 2.55	$ 2.36	$ 7.38	$ 6.85
Diluted (in dollars per share)	$ 2.55	$ 2.35	$ 7.36	$ 6.83
Shares of Common Stock Outstanding During the Period:
Average (in shares)	301.9	308.8	303.4	310.6
Average assuming dilution (in shares)	303.0	309.7	304.5	311.6

Amortization and Impairment of Intangible Assets

No definition available.

Name:	itw_AmortizationandImpairmentofIntangibleAssets
Namespace Prefix:	itw_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The aggregate total costs related to selling a firm's product and services, as well as all other general, administrative, and research and development expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

+ References

No definition available.