COMMERCIAL MORTGAGE LOANS HELD-FOR-INVESTMENT Summary of Commercial Loan Risk Ratings (Details)	12 Months Ended
	Dec. 31, 2018 USD ($) mortgage_loan	Dec. 31, 2017 USD ($)
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment	$ 555,172,891	$ 0
Commercial Real Estate Portfolio Segment
Financing Receivable, Recorded Investment [Line Items]
Number Of Loans | mortgage_loan	44
Unpaid Principal Balance	$ 555,172,891	0
Loans held for investment	$ 555,172,891	$ 0
Commercial Real Estate Portfolio Segment | Risk Rating, 1
Financing Receivable, Recorded Investment [Line Items]
Number Of Loans | mortgage_loan	0
Unpaid Principal Balance	$ 0
Loans held for investment	$ 0
Commercial Real Estate Portfolio Segment | Risk Rating, 2
Financing Receivable, Recorded Investment [Line Items]
Number Of Loans | mortgage_loan	5
Unpaid Principal Balance	$ 51,589,000
Loans held for investment	$ 51,589,000
Commercial Real Estate Portfolio Segment | Risk Rating, 3
Financing Receivable, Recorded Investment [Line Items]
Number Of Loans | mortgage_loan	34
Unpaid Principal Balance	$ 455,323,082
Loans held for investment	$ 455,323,082
Average risk rating, percentage	91.30%
Commercial Real Estate Portfolio Segment | Risk Rating, 4
Financing Receivable, Recorded Investment [Line Items]
Number Of Loans | mortgage_loan	5
Unpaid Principal Balance	$ 48,260,809
Loans held for investment	$ 48,260,809
Commercial Real Estate Portfolio Segment | Risk Rating, 5
Financing Receivable, Recorded Investment [Line Items]
Number Of Loans | mortgage_loan	0
Unpaid Principal Balance	$ 0
Loans held for investment	$ 0