Represents the amount of economic interest in an investment that may be obtained by an entity.

No definition available.

Name:	ctgo_AmountOfEconomicInterestThatMayBeObtained
Namespace Prefix:	ctgo_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of cumulative contributions in an equity method investment if additional contributions are made by the investing entity.

+ References

No definition available.

+ Details

Name:	ctgo_EquityMethodInvestmentCumulativeContributionsIfAdditionalContributionsMade
Namespace Prefix:	ctgo_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents the amount of initial investment for the purpose of funding exploration activity.

+ References

No definition available.

+ Details

Name:	ctgo_InitialInvestmentToFundExplorationActivity
Namespace Prefix:	ctgo_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents the agreed fair value of the contributed assets pertaining to an investment.

+ References

No definition available.

+ Details

Name:	ctgo_InvestmentsInJointVenturesContributedAssetsValue
Namespace Prefix:	ctgo_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents the percentage of economic interest in an investment that may be obtained by an entity.

+ References

No definition available.

+ Details

Name:	ctgo_PercentageOfEconomicInterestThatMayBeObtained
Namespace Prefix:	ctgo_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the amount of reimbursement paid to the entity during the period from the co-founder of a joint venture.

+ References

No definition available.

+ Details

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

- Definition

This element represents the aggregate cost of investments 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 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- 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

+ Details

Name:	us-gaap_EquityMethodInvestmentOwnershipPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

Name:	us-gaap_MinorityInterestOwnershipPercentageByParent
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The cash outflow associated with the investment in or advances to an entity in which the reporting entity shares control of the entity with another party or group.

+ 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

+ Details

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

- Definition

Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 5A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=108788376&loc=SL6759159-111685

+ Details

Name:	us-gaap_VariableInterestEntityOwnershipPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	srt_OwnershipAxis=ctgo_TheJointVentureCompanyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=ctgo_TheJointVentureCompanyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=ctgo_RoyalGoldMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Note 8 - Formation of Joint Venture Company (Details Textual) - USD ($)		6 Months Ended	48 Months Ended
	Jan. 08, 2015	Dec. 31, 2018	Dec. 31, 2018	Apr. 26, 2018	Jan. 08, 2018
The Joint Venture Company [Member]
Noncontrolling Interest, Ownership Percentage by Parent	100.00%
The Joint Venture Company [Member]
Equity Method Investment, Aggregate Cost	$ 1,400,000	$ 1,400,000	$ 1,400,000
Investments in Joint Ventures, Contributed Assets Value	45,700,000
Equity Method Investment, Ownership Percentage		60.00%	60.00%	60.00%
The Joint Venture Company [Member] \| Royal Gold [Member]
Initial Investment to Fund Exploration Activity	$ 5,000,000
Variable Interest Entity, Qualitative or Quantitative Information, Ownership Percentage	0.00%
Reimbursement from Joint Venture Co-founder	$ 750,000
Percentage of Economic Interest That May Be Obtained	40.00%
Amount of Economic Interest That May Be Obtained					$ 30,000,000
Equity Method Investment, Cumulative Contributions if Additional Contributions Made				$ 30,000,000
Equity Method Investment, Ownership Percentage		40.00%	40.00%	40.00%
Payments to Acquire Interest in Joint Venture		$ 33,600,000	$ 33,600,000