VARIABLE INTEREST ENTITIES (Schedule of Variable Interest Entities) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
VARIABLE INTEREST ENTITIES [Abstract]
Assets recorded related to VIEs	$ 316,254	$ 549,684
Unfunded loan commitments to VIEs	52,450	136,104
Maximum exposure to loss	$ 368,704	$ 685,788

Unfunded loan commitment supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

No definition available.

+ Details

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Namespace Prefix:	jcap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Difference between the carrying amount of assets and liabilities in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the variable interest entity (VIE) and the reporting entity's maximum exposure to loss as a result of its involvement with the VIE, where the reporting entity is not the VIE's primary beneficiary.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=118582676&loc=d3e5728-111685

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Carrying amount of the assets in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the Variable Interest Entity (VIE), where the reporting entity is not the VIE's primary beneficiary.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph a
-URI http://asc.fasb.org/extlink&oid=118582676&loc=d3e5728-111685

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
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