Investments - Schedule of Loans Receivable, Net of Premium and Allowance for Loan Losses (Details) - USD ($) $ in Thousands |
Sep. 30, 2019 |
Dec. 31, 2018 |
|---|---|---|
| Loans and Leases Receivable Disclosure [Line Items] | ||
| Loans and leases receivable, gross | $ 35,439 | $ 44,742 |
| Total loans receivable, net | 36,570 | 47,044 |
| Mortgage Loans | ||
| Loans and Leases Receivable Disclosure [Line Items] | ||
| Loans and leases receivable, gross | 33,440 | 42,660 |
| Mortgage loans - premiums, net of amortization | 1,308 | 2,527 |
| Allowance for loan losses | 0 | 0 |
| Total loans receivable, net | 34,748 | 45,187 |
| Other Notes Receivable | ||
| Loans and Leases Receivable Disclosure [Line Items] | ||
| Loans and leases receivable, gross | 1,999 | 2,082 |
| Mortgage loans - premiums, net of amortization | (177) | (225) |
| Allowance for loan losses | 0 | 0 |
| Total loans receivable, net | $ 1,822 | $ 1,857 |