Fair Value Measurements - Fair Value Inputs of Long-Lived Assets Held and Used and Held for Sale (Details)
|
6 Months Ended |
12 Months Ended |
|
Jun. 30, 2018
ft²
$ / ft²
|
Dec. 31, 2017
ft²
$ / ft²
|
| Fair Value Estimated Using Comparable Properties | Retail |
|
|
| Impaired Long-Lived Assets Held and Used [Line Items] |
|
|
| Square footage (in sqft) | ft² |
0
|
364,940
|
| Fair Value Estimated Using Comparable Properties | Retail | Weighted Average |
|
|
| Impaired Long-Lived Assets Held and Used [Line Items] |
|
|
| Weighted average price (in USD per sqft) |
0.00
|
55.68
|
| Fair Value Estimated Using Comparable Properties | Retail | Minimum |
|
|
| Impaired Long-Lived Assets Held and Used [Line Items] |
|
|
| Weighted average price (in USD per sqft) |
|
13.66
|
| Fair Value Estimated Using Comparable Properties | Retail | Maximum |
|
|
| Impaired Long-Lived Assets Held and Used [Line Items] |
|
|
| Weighted average price (in USD per sqft) |
|
305.05
|
| Fair Value Estimated Using Comparable Properties | Industrial |
|
|
| Impaired Long-Lived Assets Held and Used [Line Items] |
|
|
| Square footage (in sqft) | ft² |
0
|
370,824
|
| Fair Value Estimated Using Comparable Properties | Industrial | Weighted Average |
|
|
| Impaired Long-Lived Assets Held and Used [Line Items] |
|
|
| Weighted average price (in USD per sqft) |
0.00
|
5.35
|
| Fair Value Estimated Using Comparable Properties | Industrial | Minimum |
|
|
| Impaired Long-Lived Assets Held and Used [Line Items] |
|
|
| Weighted average price (in USD per sqft) |
|
3.30
|
| Fair Value Estimated Using Comparable Properties | Industrial | Maximum |
|
|
| Impaired Long-Lived Assets Held and Used [Line Items] |
|
|
| Weighted average price (in USD per sqft) |
|
8.56
|
| Fair Value Estimated Using Comparable Properties | Office |
|
|
| Impaired Long-Lived Assets Held and Used [Line Items] |
|
|
| Square footage (in sqft) | ft² |
0
|
161,346
|
| Fair Value Estimated Using Comparable Properties | Office | Weighted Average |
|
|
| Impaired Long-Lived Assets Held and Used [Line Items] |
|
|
| Weighted average price (in USD per sqft) |
0.00
|
40.14
|
| Fair Value Estimated Using Comparable Properties | Office | Minimum |
|
|
| Impaired Long-Lived Assets Held and Used [Line Items] |
|
|
| Weighted average price (in USD per sqft) |
|
24.82
|
| Fair Value Estimated Using Comparable Properties | Office | Maximum |
|
|
| Impaired Long-Lived Assets Held and Used [Line Items] |
|
|
| Weighted average price (in USD per sqft) |
|
244.86
|
| Fair Value Estimated Using Listing Price or Broker Opinion of Value | Retail |
|
|
| Impaired Long-Lived Assets Held and Used [Line Items] |
|
|
| Weighted average price (in USD per sqft) |
232.81
|
88.89
|
| Square footage (in sqft) | ft² |
16,000
|
22,500
|
| Fair Value Estimated Using Listing Price or Broker Opinion of Value | Retail | Weighted Average |
|
|
| Impaired Long-Lived Assets Held and Used [Line Items] |
|
|
| Weighted average price (in USD per sqft) |
232.81
|
88.89
|
| Fair Value Estimated Using Listing Price or Broker Opinion of Value | Office |
|
|
| Impaired Long-Lived Assets Held and Used [Line Items] |
|
|
| Weighted average price (in USD per sqft) |
225.04
|
0.00
|
| Square footage (in sqft) | ft² |
5,999
|
0
|
| Fair Value Estimated Using Listing Price or Broker Opinion of Value | Office | Weighted Average |
|
|
| Impaired Long-Lived Assets Held and Used [Line Items] |
|
|
| Weighted average price (in USD per sqft) |
225.04
|
0.00
|
| Fair Value Estimated Using Signed Purchase and Sale Agreement | Retail |
|
|
| Impaired Long-Lived Assets Held and Used [Line Items] |
|
|
| Square footage (in sqft) | ft² |
0
|
150,376
|
| Fair Value Estimated Using Signed Purchase and Sale Agreement | Retail | Weighted Average |
|
|
| Impaired Long-Lived Assets Held and Used [Line Items] |
|
|
| Weighted average price (in USD per sqft) |
0.00
|
230.52
|
| Fair Value Estimated Using Signed Purchase and Sale Agreement | Retail | Minimum |
|
|
| Impaired Long-Lived Assets Held and Used [Line Items] |
|
|
| Weighted average price (in USD per sqft) |
|
55.30
|
| Fair Value Estimated Using Signed Purchase and Sale Agreement | Retail | Maximum |
|
|
| Impaired Long-Lived Assets Held and Used [Line Items] |
|
|
| Weighted average price (in USD per sqft) |
|
346.23
|
| Fair Value Estimated Using Signed Purchase and Sale Agreement | Industrial |
|
|
| Impaired Long-Lived Assets Held and Used [Line Items] |
|
|
| Square footage (in sqft) | ft² |
0
|
223,747
|
| Fair Value Estimated Using Signed Purchase and Sale Agreement | Industrial | Weighted Average |
|
|
| Impaired Long-Lived Assets Held and Used [Line Items] |
|
|
| Weighted average price (in USD per sqft) |
0.00
|
37.09
|
| Fair Value Estimated Using Signed Purchase and Sale Agreement | Industrial | Minimum |
|
|
| Impaired Long-Lived Assets Held and Used [Line Items] |
|
|
| Weighted average price (in USD per sqft) |
|
24.02
|
| Fair Value Estimated Using Signed Purchase and Sale Agreement | Industrial | Maximum |
|
|
| Impaired Long-Lived Assets Held and Used [Line Items] |
|
|
| Weighted average price (in USD per sqft) |
|
54.21
|