Investments - Schedule of Loans Receivable, Net of Premium and Allowance for Loan Losses (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable, net	$ 26,405	$ 30,093
Mortgage loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable-principal	26,405	30,778
Allowance for loan losses	0	(1,299)
Total loans receivable, net	26,405	29,479
Other Notes
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable-principal	12,500	34,416
Allowance for loan losses	$ (12,500)	$ (33,802)

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount, before allowance and fees, of loans and leases receivable. Excludes loans and leases covered under loss sharing agreements.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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