LOANS HELD FOR INVESTMENT (HFI) AND LOANS HELD FOR SALES (HFS) (Narrative) (Details) - USD ($) $ in Thousands		9 Months Ended	12 Months Ended
Apr. 01, 2019	Sep. 30, 2019	Dec. 31, 2018	Jun. 30, 2019
Held-for-investment loans, nonaccrual status, unpaid principal balance		$ 1,100	$ 1,100
Loans Receivable Held-for-Investment, Carrying Value, Nonaccruing Interest		300	300
Loans Receivable, Held-For-Sale, Cost Basis		6,000	6,000
HFI loans that were 90 days or more past due and still accruing interest		0	0
Loans Receivable Held-for-sale, Net, Not Part of Disposal Group		0	0
Carrying value of Loan receivable		$ 87,267	67,299
Solar Development Lending, LLC [Member]
Equity method investment, ownership percentage	5.40%	44.70%		5.10%
Payments to acquire equity method investments	$ 11,300
Carrying value of Loan receivable	$ 11,300	$ 20,000
Effective Interest rate of Loan receivable		17.30%
Loan Origination Commitments [Member]
Unfunded loan commitments		$ 0	$ 0

Represents the unpaid principal balance on held-for-investment loans that have been placed on non-accrual status.

No definition available.

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- Definition

The effective rate of interest on loan receivable.

+ References

No definition available.

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- Definition

Loans Receivable Held-for-Investment, Carrying Value, Not Accruing Interest

+ References

No definition available.

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- Definition

Loans Receivable, Held-For-Sale, Cost Basis

+ References

No definition available.

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- Definition

Unfunded Loan Origination Commitments

+ References

No definition available.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

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- Definition

Recorded investment in financing receivables that are 90 days or more past due and still accruing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5111-111524

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- Definition

Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

Amount, after allowance for bad debt, of loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

+ References

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- Definition

The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3213-108585

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