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

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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Period Type:	instant

- Definition

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

+ References

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- Definition

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.

+ References

No definition available.

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- Definition

Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

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-SubTopic 10
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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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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

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.

+ References

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

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Mortgages and Notes Payable - Credit Agreement Terms (Details) - USD ($)	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Aug. 01, 2019	Jul. 31, 2019	Feb. 28, 2019	Jan. 31, 2019
Debt Instrument [Line Items]
Debt satisfaction gains (charges), net		$ (4,517,000)	$ (2,596,000)	$ 6,196,000
Unsecured Term Loan
Debt Instrument [Line Items]
Debt issuance costs, gross		2,561,000	$ 1,267,000
Unsecured Revolving Credit Facility, Expiring August 2019 \| Revolving Credit Facility
Debt Instrument [Line Items]
Face amount		600,000,000
Line of credit maximum borrowing capacity							$ 600,000,000
Debt satisfaction gains (charges), net	$ (93,000)
Revolving credit facility borrowings		0
Line of credit remaining borrowing capacity		600,000,000						$ 505,000,000
Unsecured Term Loan, Expiring January 2025 \| Unsecured Term Loan
Debt Instrument [Line Items]
Debt interest rate percentage						2.732%
Unsecured Term Loan, Expiring January 2021 \| Unsecured Term Loan
Debt Instrument [Line Items]
Face amount		$ 300,000,000
London Interbank Offered Rate (LIBOR) \| Unsecured Revolving Credit Facility, Expiring August 2019 \| Revolving Credit Facility
Debt Instrument [Line Items]
Interest rate stated percentage rate range minimum excluding LIBOR		0.90%
London Interbank Offered Rate (LIBOR) \| Unsecured Term Loan, Expiring January 2021 \| Unsecured Term Loan
Debt Instrument [Line Items]
Interest rate stated percentage rate range minimum excluding LIBOR		1.00%
Designated as Hedging Instrument \| Cash Flow Hedging \| Interest Rate Swap
Debt Instrument [Line Items]
Derivative notional amount		$ 300,000,000			$ 300,000,000	$ 300,000,000