The percentage of interest in equity method investment sold during the period.

No definition available.

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Namespace Prefix:	ctgo_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The equity interest of other holders in equity method investment.

+ References

No definition available.

+ Details

Name:	ctgo_EquityMethodInvestmentOwnershipPercentageByOtherOwner
Namespace Prefix:	ctgo_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The number of shares of an equity method investment owned.

+ References

No definition available.

+ Details

Name:	ctgo_EquityMethodInvestmentOwnershipShares
Namespace Prefix:	ctgo_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents an entity's ownership percentage in a company as of the balance sheet date.

+ References

No definition available.

+ Details

Name:	ctgo_PercentageOwnershipInCompany
Namespace Prefix:	ctgo_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The amount of prepayments for reimbursement from the sale of an equity method investment.

+ References

No definition available.

+ Details

Name:	ctgo_SaleOfEquityMethodInvestmentPrepaymentOfReimbursement
Namespace Prefix:	ctgo_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of shares received from the sale of equity method investments.

+ References

No definition available.

+ Details

Name:	ctgo_SharesReceivedFromSaleOfEquityMethodInvestments
Namespace Prefix:	ctgo_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- 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://www.xbrl.org/2003/role/disclosureRef
-Topic 323
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481687/323-10-50-3

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of gain (loss) on sale or disposal of an equity method investment.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-28

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(b)(7)(c))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(b)(9)(a))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2

+ Details

Name:	us-gaap_EquityMethodInvestmentRealizedGainLossOnDisposal
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 323
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481664/323-10-45-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 323
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481687/323-10-50-3

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(10))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 25
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-25

+ Details

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

- Definition

The cash inflow associated with the sale of 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
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-12

+ Details

Name:	us-gaap_ProceedsFromSaleOfEquityMethodInvestments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=ctgo_TheJointVentureCompanyMember
Namespace Prefix:
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- Details

Name:	srt_CounterpartyNameAxis=ctgo_KGMiningMember
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- Details

Name:	dei_LegalEntityAxis=ctgo_COREAlaskaMember
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- Details

Name:	dei_LegalEntityAxis=ctgo_KGMiningMember
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- Details

Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=ctgo_RoyalAlaskaLLCMember
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Note 9 - Sales Transaction With KG Mining (Details Textual) - USD ($)	Sep. 30, 2020	Mar. 31, 2023	Jun. 30, 2022	Jun. 29, 2021	Sep. 29, 2020
Equity Method Investments		$ 0	$ 0
The Joint Venture Company [Member]
Equity Method Invesment, Interest Sold, Percent	30.00%
Equity Method Investment, Ownership Percentage		30.00%			30.00%
Equity Method Investment, Realized Gain (Loss) on Disposal, Total	$ 39,600,000
Equity Method Investments	$ 0	$ 0	$ 0	$ 0
The Joint Venture Company [Member] \| KG Mining [Member]
Equity Method Investment, Ownership Percentage by Other Owner	70.00%
CORE Alaska [Member] \| The Joint Venture Company [Member]
Equity Method Invesment, Interest Sold, Percent	30.00%
Proceeds from Sale of Equity Method Investments	$ 32,400,000
Shares Received From Sale of Equity Method Investments (in shares)	809,744
Sale of Equity Method Investment, Prepayment of Reimbursement	$ 1,200,000
Equity Method Investment, Ownership Percentage	30.00%
KG Mining [Member] \| Royal Alaska LLC [Member]
Percentage Ownership in Company	100.00%
Equity Method Investment, Ownership, Shares (in shares)	809,744
Royal Alaska LLC [Member] \| The Joint Venture Company [Member]
Equity Method Investment, Ownership Percentage	40.00%