INVESTMENTS - Mortgage loans (Details) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Mortgage Loans held-for-investment:
Commercial	$ 298,650,000	$ 325,062,000
Total Mortgage Loans held-for-investment	$ 298,650,000	$ 325,062,000
% of Total
Commercial	100.00%	100.00%
Total Mortgage Loans held-for-investment	100.00%	100.00%
Debt service coverage ratio, in excess of	2.2
Loan-to-value ratio, percent (less than)	60.00%
Credit losses on commercial mortgage loans	$ 0	$ 0

Loans Held For Investment, Commercial, Percent

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Loans Held For Investment, Percent [Abstract]

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Total Mortgage Loans held-for-investment, Percent

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- Definition

Weighted Average Debt Service Coverage Ratios

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Weighted average loan-to-value ratios

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- Definition

Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(3)
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Amount before allowance of commercial loans issued to businesses to acquire, develop, construct, improve, or refinance land or building. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans covered under loss sharing agreements.

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The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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