Intangible Assets (Summary of Intangible Asset's) (Additional Information) (Details)	3 Months Ended		12 Months Ended
	Mar. 29, 2018 USD ($) shares	Mar. 30, 2017 USD ($) Theater shares	Dec. 27, 2018 USD ($)	Dec. 28, 2017 USD ($)	Dec. 29, 2016 USD ($)
Finite-Lived Intangible Assets [Line Items]
Common membership units issued (in shares) \| shares	2,821,710	2,351,029
Common membership units issued (in shares) \| shares	3,736,860
Common membership units returned (in shares) \| shares	915,150
Increase (decrease) in intangible assets, net \| $	$ 15,900,000	$ 201,800,000
Purchase of intangible assets from affiliate \| $			$ 100,000.0	$ 2,100,000	$ 2,300,000
Payments from related parties, theater payments \| $			22,700,000	12,900,000	$ 2,400,000
Software [Member]
Finite-Lived Intangible Assets [Line Items]
Purchase of intangible assets from affiliate \| $				200,000
AMC \| NCM, Inc. and NCM LLC, MOU with AMC to Effectuate Aspects of Final Judgment [Member]
Finite-Lived Intangible Assets [Line Items]
Percentage increase (decrease) in theater attendance for Common Unit adjustment to occur		9.50%
Number of theaters required to transfer advertising rights to another advertising provider \| Theater		17
Common membership units surrendered \| shares		4,657,673
Common membership units surrendered under adjustment for divested theaters \| shares		2,850,453
Common membership units surrendered under compensate for lost operating income for divested theaters \| shares		1,807,220
Common membership units surrendered, value, under compensate for lost operating income for divested theaters \| $		$ 25,000,000
Compensate for lost operating income for divested theaters, term		10 years
AMC;s Acquisition of Carmike Cinemas, Inc [Member]
Finite-Lived Intangible Assets [Line Items]
Common membership units issued (in shares) \| shares		18,425,423
AMC and Cinemark [Member]
Finite-Lived Intangible Assets [Line Items]
Increase (decrease) in intangible assets, net \| $			0	0
Payments from related parties, theater payments \| $			$ 0	$ 0

National CineMedia, LLC 10-K