Note 10 - Fair Value of Financial Instruments (Details Textual) - USD ($)	Mar. 31, 2020	Dec. 31, 2019
Variable Interest Rate [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Debt instrument, fair value	$ 93,800,000	$ 93,800,000
Fixed Interest Rate [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Debt instrument, fair value	19,100,000	17,200,000
Debt instrument, estimated fair value	18,300,000	17,200,000
Interest Rate Swap [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value of interest rate swap liability	800,000	100,000
Maximum [Member] | Interest Rate Cap [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value of interest rate cap assets	$ 100,000	$ 100,000