Loans Receivable (Details) $ in Thousands		1 Months Ended		9 Months Ended		12 Months Ended
		Jul. 31, 2015 USD ($)	Jun. 30, 2015 USD ($)	Sep. 30, 2015 USD ($) class_of_financing	Sep. 30, 2014 USD ($)	Dec. 31, 2014 USD ($) portfolio_segment type_of_financing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan carrying-value	[1]			$ 95,806		$ 105,635
Number of types of financing receivable | type_of_financing						2
Number of portfolio segments | portfolio_segment						1
Number of classes of financing receivable | class_of_financing				1
Westmont, Illinios [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan carrying-value	[1],[2]			$ 0		$ 12,152
Interest rate of mortgage loans	[2]			6.45%		6.45%
Cash acquired through foreclosure		$ 2,521
Litigation settlement, amount		$ 1,400
Impaired financing receivable, interest income, cash basis method				$ 0	$ 1,284
Southfield, Michigan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan carrying-value	[1],[3]			$ 0		$ 3,296
Interest rate of mortgage loans	[3]			4.55%		4.55%
Impaired financing receivable, interest income, cash basis method				$ 14
Kennewick, Washington [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan carrying-value	[1]			$ 85,451		$ 85,254
Interest rate of mortgage loans				9.00%		9.00%
Oklahoma City, Oklahoma [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan carrying-value	[1],[4]			$ 8,420		$ 0
Interest rate of mortgage loans	[4]			11.50%		11.50%
Oklahoma City, Oklahoma [Member] | Tenant-in-Common [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan carrying-value			$ 8,420
Ownership percentage			40.00%
Austin, Texas [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan carrying-value	[1],[5]			$ 0		$ 2,800
Interest rate of mortgage loans	[5]			16.00%		16.00%
Proceeds from Collection of Loans Receivable			$ 3,545
Other Loan Locations [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan carrying-value	[1]			$ 1,935		$ 2,133
Interest rate of mortgage loans				8.00%		8.00%

[1] Loan carrying value includes accrued interest and is net of origination costs and loan losses, if any.

[2] In July 2015, the Company acquired the office property collateral and $2,521of cash collateral and received $1,400 in full settlement of its claim against the borrower. During the nine months ended September 30, 2015 and 2014, the Company recognized $0 and $1,284 of interest income relating to the impaired loan, respectively

[3] In April 2015, the Company acquired the office property collateral from the borrower. In 2015, the Company recognized $14 of interest income relating to the impaired loan

[4] In June 2015, the Company loaned a tenant-in-common $8,420. The loan is secured by the tenant-in-common's interest in an office property, in which the Company has a 40% interest.

[5] In June 2015, the borrower satisfied the loan with a $3,545 payment, which included yield maintenance.