Summary of Significant Accounting Policies - Schedule of Earnings per Share, Basic and Diluted (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 25, 2022	Dec. 26, 2021
Basic
Net earnings attributable to Hasbro, Inc., basic	$ (1,489.3)	$ 203.5	$ 428.7
Average shares outstanding, basic (in shares)	138.8	138.7	138.0
Net earnings attributable to Hasbro, Inc. (in dollars per share)	$ (10.73)	$ 1.47	$ 3.11
Diluted
Net earnings attributable to Hasbro, Inc., diluted	$ (1,489.3)	$ 203.5	$ 428.7
Effect of dilutive securities:
Average shares outstanding, basic (in shares)	138.8	138.7	138.0
Options and other share-based awards (in shares)	0.0	0.2	0.4
Equivalent shares, diluted (in shares)	138.8	138.9	138.4
Net earnings attributable to Hasbro, Inc. (in dollars per share)	$ (10.73)	$ 1.46	$ 3.10