Statement of Income (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Income Statement [Abstract]
Operating Revenue	$ 3,939	$ 3,544
Cost of revenue	2,357	2,039
Selling, administrative, and research and development expenses	652	566
Amortization and impairment of intangible assets	35	34
Operating Income	895	905
Interest expense	(48)	(52)
Other income (expense)	14	12
Income Before Taxes	861	865
Income Taxes	199	194
Net Income	$ 662	$ 671
Net Income Per Share:
Basic (in dollars per share)	$ 2.12	$ 2.12
Diluted (in dollars per share)	$ 2.11	$ 2.11
Shares of Common Stock Outstanding During the Period:
Average (in shares)	312.5	316.6
Average assuming dilution (in shares)	313.7	317.9

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.