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Note 2 - Acquisitions and Divestitures - Schedule of Business Acquisition Assets and Liabilities of Lattner Entertainment Group Illinois (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jun. 01, 2018	Dec. 31, 2017
Goodwill	$ 971,287	$ 1,083,287	$ 1,062,102		$ 888,224
Lattner Entertainment Group Illinois, LLC [Member]
Property and equipment	9,496
Intangible assets	58,000
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net, Total				$ 110,500
Revision of Prior Period, Adjustment [Member] \| Lattner Entertainment Group Illinois, LLC [Member]
Current assets	10,638
Property and equipment	9,496
Other assets	2,933
Intangible assets	58,000
Total acquired assets	81,067
Current liabilities	1,062
Total liabilities assumed	1,062
Net identifiable assets acquired	80,005
Goodwill	30,529
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net, Total	$ 110,534