Notes Payable and Unsecured Credit Facilities (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($)
Debt Instrument [Line Items]
Line of Credit Facility, Interest Rate Description	LIBOR plus 0.875%
Debt instrument, interest rate, basis for effective rate	91.4
Line of Credit Facility, Commitment Fee Amount	0.15%
Debt Instrument, Interest Rate Terms	LIBOR plus 0.95%
Debt maturing over the next twelve months	$ 50,359
Interest Rate Swap [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate swap stated	2.00%
Non-Recourse Mortgage Loan [Member]
Debt Instrument [Line Items]
Debt maturing over the next twelve months	$ 39,100
Line of Credit [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, basis for effective rate	LIBOR plus 0.875%
Line of Credit [Member] \| Term Loans [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, basis for effective rate	LIBOR plus 0.95%
Line of Credit [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt instrument basis spread on variable rate	0.875%
Line of Credit [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Term Loans [Member]
Debt Instrument [Line Items]
Debt instrument basis spread on variable rate	0.95%
Accordion Feature [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 1,250,000

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

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Description of any adjustments made to the stated rate to determine the effective rate.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets.

+ References

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

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Description of the interest rate for the amounts borrowed under the credit facility, including the terms and the method for determining the interest rate (for example, fixed or variable, LIBOR plus a percentage, increasing rate, timing of interest rate resets, remarketing provisions).

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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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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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