Investments - Schedule of Loans Receivable, Net of Premium (Details) - USD ($)
$ in Thousands
Mar. 31, 2015
Dec. 31, 2014
Loans and Leases Receivable Disclosure [Line Items]    
Loans receivable, net $ 107,403 $ 109,425
Mortgage Receivable    
Loans and Leases Receivable Disclosure [Line Items]    
Loans receivable, gross 95,204 96,594
Loan premium 11,833 12,452
Loans receivable, net 107,037 109,046
Notes Receivable    
Loans and Leases Receivable Disclosure [Line Items]    
Loans receivable, gross $ 366 $ 379