Impaired, nonaccrual and default loans outstanding.

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- Definition

Balance of the senior loan that remains held for sale.

+ References

No definition available.

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- Definition

Number Of Real Estate Properties Purchased

+ References

No definition available.

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- Definition

Number Of Real Estate Properties Sold

+ References

No definition available.

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- Definition

Weighted Average Amortization Period

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No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
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- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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- Definition

The gains (losses) included in earnings that represent the difference between the sale price and the carrying value of loans made to finance real estate acquisitions. This element refers to the gain (loss) and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

+ References

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- Definition

The net gain (loss) resulting from sales and other disposals of real estate owned for investment purposes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The face amount of loans that will be sold to other entities.

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- Definition

The number of real estate properties owned as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

The cash inflow from proceeds From Sales of Wholly Owned Real Estate and Real Estate Acquired in Settlement of Loans.

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-Name Accounting Standards Codification
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- Definition

Amount of expense related to loss from loan transactions.

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-Name Accounting Standards Codification
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- Definition

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.

+ References

No definition available.

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COMMERCIAL REAL ESTATE INVESTMENTS - Additional Information (Details)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2018 USD ($) property	Jun. 30, 2017 USD ($) property	Jun. 30, 2018 USD ($) property	Jun. 30, 2017 USD ($) property	Dec. 31, 2017 USD ($)	Dec. 11, 2015 USD ($) property
Real Estate Properties [Line Items]
Outstanding impaired loans, nonaccrual loans, and loans in default	$ 0		$ 0		$ 0
Allowance for loan losses			$ 0		$ 0
Loans receivable with variable rates of interest			85.00%		85.00%
Number of commercial real estate acquired (property) \| property	0	0	0	0
Number of wholly owned real estate properties sold (property) \| property				1
Proceeds from sale of wholly-owned triple net leased properties				$ 12,000,000
Gain on sale of wholly-owned triple net leased properties				5,100,000
Weighted average amortization period for intangible assets and liabilities			4 years 4 months 15 days
Eight Class AB Office Properties In Orange Country California \| California
Real Estate Properties [Line Items]
Number of real estate properties (property) \| property						8
Commercial Mortgage Loan
Real Estate Properties [Line Items]
Debt issued	$ 312,500,000		$ 312,500,000		$ 312,500,000
Commercial Mortgage Loan \| Eight Class AB Office Properties In Orange Country California \| California
Real Estate Properties [Line Items]
Debt issued						$ 335,000,000.0
Gain or loss on sales of senior loan				0
Commercial Mortgage Loan \| Eight Class AB Office Properties In Orange Country California \| California \| Senior Loans
Real Estate Properties [Line Items]
Remaining senior loans held for sale		$ 115,000,000		115,000,000
Remaining senior loans held for sale, net of origination fees		114,400,000		114,400,000
General and Administrative Expense
Real Estate Properties [Line Items]
Depreciation expense	$ 3,600,000	$ 3,900,000	$ 7,400,000	$ 7,800,000