Note 2 - Acquisitions and Divestitures - Schedule of Acquired Intangible Assets of Valley Forge Convention Center Partners (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Valley Forge Convention Center Partners, L.P. [Member]
Intangible Assets, Recorded Amount	$ 136.6
Valley Forge Convention Center Partners, L.P. [Member] | Trademarks [Member]
Intangible Assets, Recorded Amount	12.5
Valley Forge Convention Center Partners, L.P. [Member] | Gaming License Right [Member]
Intangible Assets, Recorded Amount	$ 108.0
Customer Relationships [Member]
Intangible Assets, Useful Life (Year)	3 years 6 months	7 years 3 months 18 days
Customer Relationships [Member] | Valley Forge Convention Center Partners, L.P. [Member]
Intangible Assets, Useful Life (Year)	5 years
Intangible Assets, Recorded Amount	$ 16.1