Per Share Information (Tables)

12 Months Ended

Dec. 29, 2024

Earnings Per Share [Abstract]

Schedule earnings per share

The following table sets forth the computation of basic and diluted net income per common share:

(In millions, except per share amounts)

	Fiscal Year
	2024		2023		2022
Numerator:
Numerator for basic net income per common share -
Net income attributable to ATI	$	367.8	$	410.8	$	323.5
Effect of dilutive securities:
4.75% Convertible Senior Notes due 2022	—		—		2.2
3.5% Convertible Senior Notes due 2025	5.9		10.6		11.3
Numerator for diluted net income per common share -
Net income attributable to ATI after assumed conversions	$	373.7	$	421.4	$	337.0
Denominator:
Denominator for basic net income per common share—weighted average shares	130.4		128.1		127.5
Effect of dilutive securities:
Share-based compensation	3.2		3.1		2.1
4.75% Convertible Senior Notes due 2022	—		—		2.8
3.5% Convertible Senior Notes due 2025	13.0		18.8		18.8
Denominator for diluted net income per common share—adjusted weighted average shares and assumed conversions	146.6		150.0		151.2
Basic net income attributable to ATI per common share	$	2.82	$	3.21	$	2.54
Diluted net income attributable to ATI per common share	$	2.55	$	2.81	$	2.23