Investments - Summary of Total Impairment Losses Recognized (Details) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2015 |
Sep. 30, 2014 |
Sep. 30, 2015 |
Sep. 30, 2014 |
|
| Investments in and Advances to Affiliates, Schedule of Investments [Abstract] | ||||
| Real estate and intangible asset impairment | $ 19,724 | $ 10,783 | $ 54,497 | $ 37,030 |
| Write-off of lease intangibles due to lease terminations, net | 713 | 1,910 | 1,268 | 4,509 |
| Loans receivable impairment | 338 | 0 | 338 | 0 |
| Total impairments from real estate investment net assets | 20,775 | 12,693 | 56,103 | 41,539 |
| Other impairment | 57 | 34 | 153 | 522 |
| Total impairment loss in continuing and discontinued operations | $ 20,832 | $ 12,727 | $ 56,256 | $ 42,061 |