Business Combination - Narrative (Details) £ / shares in Units, $ / shares in Units, £ in Thousands, shares in Thousands			1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	Dec. 30, 2019 USD ($) $ / shares	Dec. 30, 2019 GBP (£)	Nov. 30, 2019 USD ($) $ / shares shares	Sep. 27, 2020 USD ($)	Sep. 29, 2019 USD ($)	Sep. 27, 2020 USD ($)	Sep. 29, 2019 USD ($)	Dec. 29, 2019 USD ($)	Dec. 30, 2019 £ / shares
Business Acquisition [Line Items]
Shares issued as consideration (in shares) | shares			10,592
Goodwill				$ 3,644,118,000	$ 485,042,000	$ 3,644,118,000	$ 485,042,000	$ 494,584,000
Acquisition and related costs				5,949,000	0	165,993,000	0
Severance expense						11,554,000
Asset impairments						$ 40,878,000	0
Amortization of intangibles					9,726,000		30,778,000
Interest expense					19,105,000		57,316,000
Income tax effect, amount					683,000		8,707,000
Income tax rate, percent						19.00%
eOne
Business Acquisition [Line Items]
Payments to acquire businesses	$ 4,635,041,000	£ 2,900,000
Cash consideration per share (in dollars and GBP per share) | (per share)	$ 7.35								£ 5.60
Conversion rate (USD/GBP)	1.31
Cash consideration for shares outstanding	$ 3,658,345,000
Indebtedness redeemed as consideration for acquisition	831,130,000
Goodwill	3,149,337,000
Acquisition and related costs						$ 77,729,000
Integration related costs				4,599,000		104,283,000
Integration related costs, acceleration of stock-based compensation						47,399,000
Integration related costs, advisor fees						38,168,000
Less: Employee awards to be recorded as future stock compensation expense	$ 47,399,000
Restructuring and related cost				1,350,000		61,710,000
Severance expense				$ 1,350,000
Asset impairments						40,878,000
Acquisition costs, period cost					3,244,000		3,244,000
Other expenses					25,533,000		45,345,000
Payment for debt prepayment cost							19,812,000
eOne | Foreign Exchange Forward
Business Acquisition [Line Items]
Other expenses					$ 25,533,000		$ 25,533,000
Unsecured Committed | eOne
Business Acquisition [Line Items]
Cash consideration per share (in dollars and GBP per share) | $ / shares			$ 95.00
Term loans proceeds which financed acquisition			$ 1,000,000,000
Senior Notes | Senior Unsecured Notes
Business Acquisition [Line Items]
Proceeds from issuance of debt			975,185,000
Aggregate principal amount			$ 2,375,000,000
Entertainment, Licensing and Digital | eOne
Business Acquisition [Line Items]
Acquisition and related costs						$ 20,831,000
Minimum
Business Acquisition [Line Items]
Income tax rate, percent							21.00%
Minimum | Trademarks and Trade Names | eOne
Business Acquisition [Line Items]
Intangible asset useful life								7 years
Minimum | Films and Television Programs | eOne
Business Acquisition [Line Items]
Intangible asset useful life								3 years
Maximum
Business Acquisition [Line Items]
Income tax rate, percent							22.50%
Maximum | Trademarks and Trade Names | eOne
Business Acquisition [Line Items]
Intangible asset useful life								15 years
Maximum | Films and Television Programs | eOne
Business Acquisition [Line Items]
Intangible asset useful life								10 years