Segment Reporting - Net Revenues by Brand and Entertainment Segment (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 27, 2021	Jun. 28, 2020	Jun. 27, 2021	Jun. 28, 2020
Revenue from External Customer [Line Items]
Net revenues	$ 1,322.2	$ 860.3	$ 2,437.0	$ 1,965.9
Franchise Brands
Revenue from External Customer [Line Items]
Net revenues	649.9	376.9	1,141.4	773.4
Partner Brands
Revenue from External Customer [Line Items]
Net revenues	212.0	138.3	400.0	320.6
Hasbro Gaming
Revenue from External Customer [Line Items]
Net revenues	147.1	137.0	283.4	277.1
Emerging Brands
Revenue from External Customer [Line Items]
Net revenues	117.0	75.9	221.7	170.1
Entertainment
Revenue from External Customer [Line Items]
Net revenues	196.2	132.2	390.5	424.7
Gaming including Magic the Gathering and Monopoly
Revenue from External Customer [Line Items]
Net revenues	519.4	319.0	884.7	659.5
Entertainment
Revenue from External Customer [Line Items]
Net revenues	226.7	154.1	445.4	476.6
Entertainment | Film & TV
Revenue from External Customer [Line Items]
Net revenues	164.3	108.9	330.7	372.9
Entertainment | Family Brands
Revenue from External Customer [Line Items]
Net revenues	26.1	18.8	44.9	44.7
Entertainment | Music and Other
Revenue from External Customer [Line Items]
Net revenues	$ 36.3	$ 26.4	$ 69.8	$ 59.0