Note 7 - Leases (Details Textual) $ in Millions	Sep. 30, 2020 USD ($)
Accounts Receivable, Allowance for Credit Loss, Ending Balance	$ 72.2
Operating Lease, Weighted Average Remaining Lease Term (Year)	20 years 10 months 24 days
Operating Lease, Weighted Average Discount Rate, Percent	6.66%
Minimum [Member]
Lessee, Operating Lease, Remaining Lease Term (Year)	1 year
Maximum [Member]
Lessee, Operating Lease, Remaining Lease Term (Year)	51 years 6 months
Lessee, Operating Lease, Renewal Term (Year)	75 years
COVID 19 [Member] \| Straight-Line Rent Receivables [Member]
Accounts Receivable, Allowance for Credit Loss, Ending Balance	$ 15.1

Amount of allowance for credit loss on accounts receivable.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Remaining lease term of operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Weighted average discount rate for operating lease calculated at point in time.

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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