Note 8 - Investments in Marketable Securities - Available for Sale Marketable Equity Securities (Details) - NHI Common Stock [Member] - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
NHI Common Stock, Shares (in shares)	1,630,642	1,630,642
NHI Common Stock, Cost	$ 24,734	$ 24,734
NHI Common Stock, Fair Value	$ 132,865	$ 123,179

Balance held at close of period in number of shares.

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