Investments - Summary of Real Estate and Loan Activity, Net of Accumulated Depreciation and Amortization (Footnote) (Details) $ in Millions |
3 Months Ended |
|---|---|
|
Mar. 31, 2017
USD ($)
| |
| Investments in and Advances to Affiliates, Schedule of Investments [Abstract] | |
| Revenue producing capitalized expenditures | $ 12.6 |
| Capitalized maintenance expenditures | 0.7 |
| Accumulated depreciation and amortization associated with dispositions of real estate | $ 20.6 |