Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

Amount of hedged item in hedging relationship. Excludes hedged asset or liability.

+ References

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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.

+ 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

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- Definition

The amount of interest income and other income recognized during the period. Included in this element is interest derived from investments in debt securities, cash and cash equivalents, and other investments which reflect the time value of money or transactions in which the payments are for the use or forbearance of money and other income from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business).

+ References

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Derivative Instruments - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Mar. 08, 2018
Derivative [Line Items]
Interest and other income, net	$ 46,815	$ 26,380	$ 10,331
Interest rate cap \| LIBOR
Derivative [Line Items]
Interest and other income, net	300
Derivative, cap interest rate				2.50%
Cash flow hedging \| Designated as hedging instrument \| Interest rate swap contracts
Derivative [Line Items]
Amount of hedged item	$ 167,800
Cash flow hedging \| Designated as hedging instrument \| Interest rate swap contracts \| 1735 Market Street \| Mortgage notes
Derivative [Line Items]
Interest and other income, net			$ 200
Cash flow hedging \| Designated as hedging instrument \| Interest rate cap
Derivative [Line Items]
Derivative, notional amount				$ 400,000