AVAILABLE-FOR-SALE SECURITIES - Components of Interest Income on AFS Securities (Details) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Debt Securities, Available-for-sale [Line Items]
Coupon interest	$ 0		$ 12,152,397
Net (premium amortization)/ discount accretion	0	$ 0	(1,403,431)
Interest income	0		10,748,966
Agency
Debt Securities, Available-for-sale [Line Items]
Coupon interest	0		12,152,397
Net (premium amortization)/ discount accretion	0		(1,435,534)
Interest income	0		10,716,863
Multi-Family
Debt Securities, Available-for-sale [Line Items]
Coupon interest	0		0
Net (premium amortization)/ discount accretion	0		32,103
Interest income	$ 0		$ 32,103

Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

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Amount after accretion (amortization) of discount (premium), and investment expense, of interest income and dividend income on nonoperating securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.9)
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7(a),(b))
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

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Amount of accretion (amortization) of purchase discount (premium) on nonoperating securities.

+ References

+ Details

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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.

+ Details

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