In relation to the amount of civil penalties that can be accessed per day.

No definition available.

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- Definition

The amount of money owed due to a civil penalty.

+ References

No definition available.

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- Definition

Amount of financial assurance for decommissioning of pipeline in federal waters.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

The increase (decrease) in the financial assurance related to the pipeline.

+ References

No definition available.

+ Details

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Namespace Prefix:	bdco_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The number of pipeline rights-of-way.

+ References

No definition available.

+ Details

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- Definition

Amount of surety bonds.

+ References

No definition available.

+ Details

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- Definition

Carrying amount as of the balance sheet date of amounts received from and refundable to customers unless used by them to obtain goods and services from the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(17))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

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- Definition

Aggregate carrying amount of the estimated litigation liability for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs.

+ References

+ Details

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Balance Type:	credit
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- Definition

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 450
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483076/450-20-50-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 450
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-Section 50
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483076/450-20-50-9

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Period Type:	duration

- Definition

The amount of cash paid for the settlement of litigation or for other legal issues during the period.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 25
-Subparagraph (g)
-SubTopic 10
-Topic 230
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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

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Note 14 - Commitments and Contingencies (Details Textual)			1 Months Ended					7 Months Ended	13 Months Ended
	Jul. 21, 2025 USD ($)	Feb. 19, 2024 USD ($)	Mar. 31, 2025 USD ($)	Jan. 31, 2025 USD ($)	Nov. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Oct. 31, 2021 USD ($)	Mar. 31, 2025 USD ($)	Jan. 31, 2025 USD ($)	Sep. 30, 2025 USD ($)	Jun. 30, 2025 USD ($)	Dec. 31, 2024 USD ($)	Mar. 31, 2018 USD ($)
Surety Bonds											$ 350,000	$ 1,255,000
Blue Dolphin Pipe Line Company (BDPL) [Member] \| Bureau of Ocean Energy Management (BOEM) [Member]
Financial Assurance for Decommissioning of Pipeline in Federal Waters													$ 5,700,000
Number of Pipeline Rights-of-way													5
Financial Assurance Increase (decrease) For Pipeline													$ 4,800,000
Estimated Litigation Liability											0	0	$ 900,000
Surety Bonds											900,000	$ 900,000
Blue Dolphin Pipe Line Company (BDPL) [Member] \| Bureau of Safety and Environmental Enforcement (BSEE) [Member]
Estimated Litigation Liability											2,100,000
Rli Surety Bonds [Member]
Customer Funds			$ 1,200,000					$ 1,200,000
RLI Filing for Injunction of Payment [Member]
Customer Funds											$ 1,200,000
RLI Filing for Injunction of Payment [Member] \| Settled Litigation [Member]
Loss Contingency, Damages Sought, Value		$ 1,000,000
Payments for Legal Settlements								1,000,000
TCEQ Proposed Agreed Order [Member] \| Settled Litigation [Member]
Loss Contingency, Damages Sought, Value					$ 400,000	$ 350,000	$ 400,000
BSEE Civil Penalty G2024054 [Member] \| Blue Dolphin Pipe Line Company (BDPL) [Member] \| Bureau of Safety and Environmental Enforcement (BSEE) [Member]
Loss Contingency, Damages Sought, Value			1,000,000
Civil Penalties Per Day			3,097					3,097
BSEE Civil Penalty G2024054 [Member] \| Blue Dolphin Pipe Line Company (BDPL) [Member] \| Bureau of Safety and Environmental Enforcement (BSEE) [Member] \| Subsequent Event [Member]
Loss Contingency, Damages Sought, Value	$ 1,300,000
BSEE Civil Penalty G2024056 [Member] \| Blue Dolphin Pipe Line Company (BDPL) [Member] \| Bureau of Safety and Environmental Enforcement (BSEE) [Member]
Loss Contingency, Damages Sought, Value				$ 400,000					$ 400,000
Civil Penalties Per Day				3,097					3,097
Civil Penalty, Additional Daily Penalty				$ 3,097					$ 3,097
BSEE Civil Penalty G2024056 [Member] \| Blue Dolphin Pipe Line Company (BDPL) [Member] \| Bureau of Safety and Environmental Enforcement (BSEE) [Member] \| Forecast [Member]
Estimated Litigation Liability										$ 300,000
BSEE Civil Penalty G2024056 [Member] \| Blue Dolphin Pipe Line Company (BDPL) [Member] \| Bureau of Safety and Environmental Enforcement (BSEE) [Member] \| Subsequent Event [Member]
Loss Contingency, Damages Sought, Value	900,000
Civil Penalties Per Day	$ 3.097
BSEE Civil Penalty G2024010 [Member] \| Blue Dolphin Pipe Line Company (BDPL) [Member] \| Bureau of Safety and Environmental Enforcement (BSEE) [Member]
Loss Contingency, Damages Sought, Value			1,100,000
Estimated Litigation Liability			$ 1,100,000					$ 1,100,000