Note 9 - Notes and Mortgages Payable (Details Textual) - USD ($) $ in Thousands	1 Months Ended	6 Months Ended
Feb. 29, 2020	Jun. 30, 2021
Long-term Line of Credit, Total		$ 0
Mortgage Debt Encumbered Operating Property [Member]
Repayments of Long-term Debt, Total		137,200
Liabilities, Fair Value Adjustment		$ 1,000
Number of Real Estate Properties		25
Revolving Credit Facility [Member]
Line of Credit Facility, Current Borrowing Capacity	$ 2,000,000
Debt Instrument, Interest Rate, Effective Percentage		0.85%
Line of Credit Facility, Maximum Borrowing Capacity	$ 2,750,000
Revolving Credit Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate	0.765%
Letter of Credit [Member]
Long-term Line of Credit, Total		$ 0

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

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- Definition

Amount of addition (reduction) to the amount at which a liability could be incurred (settled) in a current transaction between willing parties.

+ References

No definition available.

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

The number of real estate properties owned as of the balance sheet date.

+ References

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- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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