Debt Instrument, Basis Spread Rate Increase Per Extension

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- Definition

Long-term Debt, Number of Additional Extensions Available

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Long-term Debt, Term of Additional Extensions

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Real Estate, Number of Properties Sold

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Area of a real estate property.

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Value of property contributed in noncash investing and financing activities.

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- Definition

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

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- Definition

Cap rate on an interest rate derivative such as an interest rate cap or collar. If market rates exceed the cap rate, a payment or receipt is triggered on the contract.

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No definition available.

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- Definition

Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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The amount of assets reported by an equity method investment of the entity.

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- Definition

The amount of liabilities reported by an equity method investment of the entity.

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- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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- Definition

Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

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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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Period between issuance and maturity of long-term debt, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of debt for which creditor does not have general recourse to the debtor but rather has recourse only to the property used for collateral in the transaction or other specific property.

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No definition available.

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The cash outflow associated with the investment in or advances to an entity in which the reporting entity shares control of the entity with another party or group.

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The cash inflow associated with the collection, including prepayments, of loans receivable issued for financing of goods and services.

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The cash inflow from the sale of formerly productive land held for sale, anything permanently fixed to it, including buildings, structures on it, and so forth.

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The fair value of transfer of mortgage payable in noncash investing or financing activities.

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Investment in and Advances to Non-Consolidated Entities - Schedule of Investment in Non-Consolidated Entities (Details) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2018 USD ($) building term	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($) a
Investments in and Advances to Affiliates [Line Items]
Investment balance	$ 70,879		$ 17,476
NNN Office Joint Venture [Member]
Investments in and Advances to Affiliates [Line Items]
Non-recourse debt	466,200
Equity method investment, assets	758,307
Equity method investment, liabilities	490,451
NNN Office Joint Venture [Member] \| Mortgages [Member]
Investments in and Advances to Affiliates [Line Items]
Non-recourse debt	$ 362,800
Long-term debt, term	3 years
Number of additional extensions available \| term	2
Term of additional extensions	1 year
Term of contract	2 years
NNN Office Joint Venture [Member] \| Mortgages [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Investments in and Advances to Affiliates [Line Items]
Basis spread on variable rate	2.00%
Basis spread rate increase per extension	0.15%
Cap interest rate	4.00%
NNN Office Joint Venture Properties [Member]
Investments in and Advances to Affiliates [Line Items]
Equity method investment, assets	$ 758,307
Equity method investment, liabilities	490,451
Transferred Property [Member] \| Office Building [Member]
Investments in and Advances to Affiliates [Line Items]
Aggregate gross disposition price	$ 967,799	$ 190,368
Transferred Property [Member] \| Office Building [Member] \| NNN Office Joint Venture Properties [Member]
Investments in and Advances to Affiliates [Line Items]
Number of properties sold \| building	21
Aggregate gross disposition price	$ 725,800
Minimum [Member]
Investments in and Advances to Affiliates [Line Items]
Ownership percentage	15.00%
Maximum [Member]
Investments in and Advances to Affiliates [Line Items]
Ownership percentage	25.00%
NNN Office Joint Venture [Member]
Investments in and Advances to Affiliates [Line Items]
Ownership percentage	20.00%
Investment balance	$ 53,571		0
NNN Office Joint Venture [Member] \| 2 of 21 Transferred Properties [Member]
Investments in and Advances to Affiliates [Line Items]
Fair value of contributed property	45,653
Payments to acquire interest in joint venture	8,053
Gain (loss) on disposition of assets	14,645
Transfer mortgage payable	$ 103,400
Etna Park 70 [Member]
Investments in and Advances to Affiliates [Line Items]
Ownership percentage	90.00%
Investment balance	$ 6,288		5,831
Payments to acquire interest in joint venture			$ 5,831
Area of real estate property \| a			151
Other Joint Ventures [Member]
Investments in and Advances to Affiliates [Line Items]
Investment balance	$ 11,020		$ 11,645
Proceeds from collection of loans receivable			$ 49,085