Business Combination - Unaudited Supplemental Pro Forma Results of Operations (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 29, 2020	Mar. 31, 2019
Business Acquisition [Line Items]
Net revenues	$ 1,105,570	$ 732,510
Pro Forma Results
Revenues		1,198,722
Net earnings attributable to Hasbro, Inc.		79,134
Net earnings attributable to Hasbro, Inc.		$ 76,405
Earnings per share attributable to Hasbro, Inc.: Diluted (in dollars per share)		$ 0.56
Earnings per share attributable to Hasbro, Inc.: Basic (in dollars per share)		$ 0.56
Operating Segments \| eOne
Business Acquisition [Line Items]
Loss before income taxes	$ (33,620)

Business Acquisition, Pro Forma, Net Income (Loss), Attributable To Parent

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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