This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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Investment in National CineMedia - Additional Information (Detail) $ / shares in Units, $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2019 USD ($) $ / shares shares	Mar. 31, 2019 USD ($) shares	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($) $ / shares shares	Jun. 30, 2018 USD ($)
Schedule Of Equity Method Investments [Line Items]
Equity in earnings	$ 8,439		$ 6,414	$ 18,843	$ 15,050
Number of additional common units of NCM received under common unit adjustment agreement \| shares		219,056
Value of common units received from NCM		$ 1,552		$ 1,552	5,012
Number of common units of NCM owned by Company \| shares	39,737,700			39,737,700
Interest in common units of NCM owned by Company	25.00%			25.00%
Investment In NCM
Schedule Of Equity Method Investments [Line Items]
Equity in earnings				$ 5,012
Common unit convertible into share of NCMI common stock, conversion ratio		1
Estimated fair value of investment using NCM's stock price	$ 260,679			$ 260,679
NCMI common stock price \| $ / shares	$ 6.56			$ 6.56
NCM
Schedule Of Equity Method Investments [Line Items]
Equity in earnings	$ 617		$ 495	$ 5,012	$ 4,511