Statement of Financial Position, Classified (Details) - USD ($)	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Finite-Lived Intangible Assets [Line Items]
Cost-method Investments, Realized Losses	$ 205,000
Document Period End Date	Mar. 31, 2020
Cost Method Investments, Original Cost	$ 10,887,000	$ 11,501,000
Prepaid Expense and Other Assets, Noncurrent	1,482,000	1,594,000
Other Assets, Noncurrent	18,236,000	19,122,000
Licensing Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Net	$ 5,867,000	$ 6,027,000