Earnings Per Common Share - Reconciliation of Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 29, 2024	Dec. 31, 2023	Dec. 25, 2022
Earnings Per Share [Abstract]
Net earnings (loss) attributable to Hasbro, Inc.	$ 385.6	$ (1,489.3)	$ 203.5
Average shares outstanding, basic (in shares)	139.4	138.8	138.7
Options and other share-based awards (in shares)	0.9	0.0	0.2
Equivalent shares, diluted (in shares)	140.3	138.8	138.9
Net earnings (loss) attributable to Hasbro, Inc. per common share, basic (in dollars per share)	$ 2.77	$ (10.73)	$ 1.47
Net earnings (loss) attributable to Hasbro, Inc. per common share, diluted (in dollars per share)	$ 2.75	$ (10.73)	$ 1.46