Summary Financial Information for National CineMedia (Detail) - NCM - USD ($) $ in Thousands	3 Months Ended
	Mar. 29, 2018	Dec. 27, 2018
Schedule Of Equity Method Investments [Line Items]
Gross revenues	$ 80,200
Operating income	11,000
Net income	$ (3,000)
Current assets		$ 172,700
Noncurrent assets		726,800
Current liabilities		115,200
Noncurrent liabilities		924,900
Members deficit		$ (140,600)