LIFO to FIFO Change in Accounting Principle - Income Statement (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 29, 2025	Mar. 30, 2024
Costs of revenue(a)	$ 596.7	$ 609.1
Gross profit	316.3	301.5
Operating Income (Loss)	150.9	149.9
Income from continuing operations before income tax	144.3	145.5
Income tax expense	35.2	33.0
Net income	109.1	112.5
Net income attributable to ITT Inc.	$ 108.4	$ 111.5
Basic earnings per share	$ 1.33	$ 1.36
Diluted earnings per share	$ 1.33	$ 1.35
Previously Reported
Costs of revenue(a)		$ 609.8
Gross profit		300.8
Operating Income (Loss)		149.2
Income from continuing operations before income tax		144.8
Income tax expense		32.8
Net income		112.0
Net income attributable to ITT Inc.		$ 111.0
Basic earnings per share		$ 1.35
Diluted earnings per share		$ 1.34
Revision of Prior Period, Adjustment
Costs of revenue(a)		$ (0.7)
Gross profit		0.7
Operating Income (Loss)		0.7
Income from continuing operations before income tax		0.7
Income tax expense		0.2
Net income		0.5
Net income attributable to ITT Inc.		$ 0.5
Basic earnings per share		$ 0.01
Diluted earnings per share		$ 0.01