Lawsuits, Claims, Commitments and Contingencies - Narrative (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017	Mar. 31, 2017
Unrecorded Unconditional Purchase Obligation [Line Items]
Bankruptcy claims dismissed by bankruptcy court			$ 14
Commitments under contracts	$ 10	$ 6
Agreement to purchase natural gas	4	14
New Road Access
Unrecorded Unconditional Purchase Obligation [Line Items]
Commitments under contracts	$ 9	$ 9
Commitments under contracts, percentage of variable component	50.00%	50.00%
Commitment based on variable components	$ 12	$ 12

Unrecorded Purchase Obligation, Percentage Of Variable Components

No definition available.

Name:	bry_UnrecordedPurchaseObligationPercentageOfVariableComponents
Namespace Prefix:	bry_
Data Type:	num:percentItemType
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Period Type:	instant

- Definition

Amount of bankruptcy claim filed that bankruptcy court has expunged.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77896938&loc=d3e25336-109308

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of the unrecorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

+ References

+ Details

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

- Definition

Amount of change that payments under a contractual obligation might vary as facts and circumstances change.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

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