Investments - Summary of Total Impairment Losses Recognized (Details) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2017 |
Sep. 30, 2016 |
Sep. 30, 2017 |
Sep. 30, 2016 |
|
| Investments in and Advances to Affiliates, Schedule of Investments [Abstract] | ||||
| Real estate and intangible asset impairment | $ 32,676 | $ 13,894 | $ 82,553 | $ 35,236 |
| Write-off of lease intangibles, net | 5,061 | 1,491 | 5,556 | 6,463 |
| Loans receivable recovery | 0 | 0 | 0 | (324) |
| Total impairments from real estate investment net assets | 37,737 | 15,385 | 88,109 | 41,375 |
| Other impairment | 0 | 22 | 0 | 21 |
| Total impairment loss | $ 37,737 | $ 15,407 | $ 88,109 | $ 41,396 |