Supplemental Cash Flow Disclosure (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015
Cash paid during the period for:
Interest	$ 110	$ 60
Income taxes		325
Non-cash transactions:
Decrease in accounts payable and accrued liabilities included in oil and gas properties	(59)	(267)
Increase in net asset retirement obligations	$ 5

Represents the increase decrease in accounts payable and accrued liabilities included in oil and gas properties. Noncash are defined as transactions during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments during the period. Part noncash refer to that portion of the transaction not resulting in cash receipts or cash payments during the period.

No definition available.

+ Details

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Namespace Prefix:	crbo_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- References

No definition available.

+ Details

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Period Type:	duration

- Definition

The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

+ References

+ Details

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

- Definition

The increase (decrease) during the reporting period in the carrying amount of asset retirement obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

+ Details

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

- Definition

The amount of cash paid for interest during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4297-108586

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3536-108585

+ Details

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- References

No definition available.

+ Details

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