Amount of restricted cash deposits made for gold lease transactions

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The leased gold outstanding and not yet returned during the period.

+ References

No definition available.

+ Details

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Data Type:	num:massItemType
Balance Type:	na
Period Type:	instant

- References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6036836-161870

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 210.5-03.8)
-URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash inflow from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with either short term or long term maturity that is collateralized (backed by pledge, mortgage or other lien in the entity's assets).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3255-108585

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LineOfCreditFacilityAxis=kgji_GoldLeaseFromCcbMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LineOfCreditFacilityAxis=kgji_ShuntianyiMember
Namespace Prefix:
Data Type:	na
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- Details

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Namespace Prefix:
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GOLD LEASE TRANSACTIONS - Additional Information (Detail) ¥ in Millions	2 Months Ended	3 Months Ended		9 Months Ended			12 Months Ended
	Feb. 28, 2017 USD ($) kg	Sep. 30, 2018 USD ($) g	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) g	Sep. 30, 2018 CNY (¥) g	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)	Oct. 10, 2018 g	Sep. 30, 2018 kg
Gold Lease Transactions [Line Items]
Proceeds from secured lines of credit					¥ 500		$ 2,000,000,000
Gold Lease Outstanding		4,974		4,974	4,974			5,356	57,476
Deposits For Gold Lease				$ 0
Wuhan Shuntianyi Investment Management Ltd [Member]
Gold Lease Transactions [Line Items]
Proceeds from secured lines of credit	$ 131,100,000
Gold Lease from CCB [Member]
Gold Lease Transactions [Line Items]
Deposits For Gold Lease							$ 0
Shuntianyi [Member]
Gold Lease Transactions [Line Items]
Gold Lease Outstanding \| kg	4,000
Gold lease transactions [Member] \| Gold Lease from CCB [Member]
Gold Lease Transactions [Line Items]
Interest expense, debt		$ 0	$ 1,159,000,000	$ 0		$ 115,972,000,000