Agreed Upon Purchase Price of Oil and Gas Property and Equipment

No definition available.

Name:	crzo_AgreedUponPurchasePriceofOilandGasPropertyandEquipment
Namespace Prefix:	crzo_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The agreed upon purchase price for the sale of oil and gas properties at the time the Company enters into a purchase and sale agreement.

+ References

No definition available.

+ Details

Name:	crzo_AgreedUponSalePriceofOilandGasPropertyandEquipment
Namespace Prefix:	crzo_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

- Definition

The cash outflow pad upon closing of disposal of long-lived, physical assets and mineral interests in oil and gas properties used for normal oil and gas operations.

+ References

No definition available.

+ Details

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Namespace Prefix:	crzo_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The total cash inflow received related to post-closing adjustments of an acquisition of oil and gas properties.

+ References

No definition available.

+ Details

Name:	crzo_CashReceivedForPostClosingAdjustmentsToAcquisitions
Namespace Prefix:	crzo_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash outflow for payments made as a deposit for the acquisition of oil and gas properties.

+ References

No definition available.

+ Details

Name:	crzo_DepositForAcquisitionOfOilAndGasProperties
Namespace Prefix:	crzo_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Estimated Aggregate Purchase Price for the acquisition of Oil and Gas Properties.

+ References

No definition available.

+ Details

Name:	crzo_EstimatedAggregatePurchasePrice
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Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_BusinessAcquisitionLineItems
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Data Type:	xbrli:stringItemType
Balance Type:	na
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- Definition

This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

+ Details

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

- Definition

This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

+ References

+ Details

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

- Definition

The cash outflow to purchase of mineral interests in oil and gas properties for use in the normal oil and gas operations and not intended for resale.

+ 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 (c)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3213-108585

+ Details

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

- Definition

The cash inflow to dispose of long-lived, physical assets and mineral interests in oil and gas properties used for normal oil and gas operations.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3179-108585

+ Details

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

- Details

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- Details

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- Details

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- Details

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- Details

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Acquisitions and Divestitures (Narrative) (Details) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended					8 Months Ended	12 Months Ended
	Feb. 28, 2018	Jan. 31, 2018	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Jul. 31, 2018	Sep. 30, 2018	Dec. 11, 2017	Nov. 20, 2017
Business Acquisition [Line Items]
Acquisition of oil and gas properties			$ 8,222			$ 0
Proceeds from divestitures of oil and gas properties, net			3,107			342,359
Devon Acquisition
Business Acquisition [Line Items]
Agreed upon Purchase Price of Oil and Gas Property and Equipment					$ 215,000
Deposit For Acquisition Of Oil And Gas Properties					21,500
Payments to Acquire Oil and Gas Property				$ 183,400
Acquisition of oil and gas properties			(8,300)
Estimated Aggregate Purchase Price			196,600
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual			4,400
Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual			$ 2,700
Eagle Ford Shale Divestiture
Business Acquisition [Line Items]
Sale Price of Oil and Gas Property and Equipment										$ 245,000
Proceeds from divestitures of oil and gas properties, net								$ 245,700
Cash Paid for Post-Closing Adjustments to Divestitures					(500)
Niobrara Divestiture
Business Acquisition [Line Items]
Sale Price of Oil and Gas Property and Equipment											$ 140,000
Proceeds from divestitures of oil and gas properties, net						$ 122,600	$ 14,000		$ 135,600
Cash Paid for Post-Closing Adjustments to Divestitures					$ (1,000)
Deposit Received Prior To Closing [Member] \| Eagle Ford Shale Divestiture
Business Acquisition [Line Items]
Proceeds from divestitures of oil and gas properties, net							$ 24,500
Cash Received At Closing [Member] \| Eagle Ford Shale Divestiture
Business Acquisition [Line Items]
Proceeds from divestitures of oil and gas properties, net		$ 211,700
Cash Received Post Closing [Member] \| Eagle Ford Shale Divestiture
Business Acquisition [Line Items]
Proceeds from divestitures of oil and gas properties, net	$ 10,000