Derivative Instruments and Hedging Activities (Details Textual) $ in Thousands	9 Months Ended
	Sep. 30, 2018 USD ($)
Derivative [Line Items]
SIFMA rate	1.56%
Minimum [Member] \| Interest rate swap agreements [Member]
Derivative [Line Items]
Derivative, term of contract	1 year
Minimum [Member] \| Interest rate caps [Member]
Derivative [Line Items]
Derivative, term of contract	1 year
Maximum [Member] \| Interest rate swap agreements [Member]
Derivative [Line Items]
Derivative, term of contract	10 years
Maximum [Member] \| Interest rate caps [Member]
Derivative [Line Items]
Derivative, term of contract	3 years
Not Designated as Hedging Instrument [Member] \| TROR [Member]
Derivative [Line Items]
Notional amount of TROR	$ 180,321
Cash Flow Hedging [Member]
Derivative [Line Items]
Loss on cash flow hedges to be reclassified within next twelve months	1,282
Fair Value Hedging [Member] \| Designated as Hedging Instrument [Member] \| TROR [Member]
Derivative [Line Items]
Notional amount of TROR	$ 676,466

Forest City Realty Trust, Inc. 10-Q