Recent Transactions (Dispositions/Rental Property Held for Sale, Net) (Narrative) (Details)
$ in Thousands |
1 Months Ended |
2 Months Ended |
12 Months Ended |
Sep. 30, 2015 |
Feb. 28, 2017
USD ($)
|
Dec. 31, 2016
USD ($)
ft²
item
property
|
Dec. 31, 2015
USD ($)
|
| Real Estate Properties [Line Items] |
|
|
|
|
| Unrealized losses on properties held for sale |
|
|
$ (7,665)
|
|
| Sales proceeds |
|
|
$ 664,481
|
$ 148,256
|
| Multi-Family Properties [Member] |
|
|
|
|
| Real Estate Properties [Line Items] |
|
|
|
|
| Number of units | item |
|
|
5,614
|
|
| Disposal Group, Held-for-sale, Not Discontinued Operations [Member] |
|
|
|
|
| Real Estate Properties [Line Items] |
|
|
|
|
| Assets held for sale, Deferred charges and other assets |
|
|
$ 1,700
|
|
| Assets held for sale, Unbilled rents receivable, net |
|
|
1,200
|
|
| Assets held for sale, Accounts payable, accrued expenses and other liabilities |
|
|
1,100
|
|
| Assets held for sale, Rents received in advance and security deposits |
|
|
1,900
|
|
| Expected assets to be written off |
|
|
2,900
|
|
| Expected liabilities to be written off |
|
|
$ 500
|
|
| Disposal Group, Held-for-sale, Not Discontinued Operations [Member] | Three Office Properties Disposed [Member] | Subsequent Event [Member] |
|
|
|
|
| Real Estate Properties [Line Items] |
|
|
|
|
| Sales proceeds |
|
$ 45,800
|
|
|
| Disposal Group, Held-for-sale, Not Discontinued Operations [Member] | Office [Member] |
|
|
|
|
| Real Estate Properties [Line Items] |
|
|
|
|
| Area of property (in square feet) | ft² |
|
|
750,000
|
|
| Number of properties held for sale | property |
|
|
8
|
|
| New Jersey Hudson River [Member] |
|
|
|
|
| Real Estate Properties [Line Items] |
|
|
|
|
| Strategic initiative period |
3 years
|
|
|
|