Represents the aggregate amount of compensation expense paid to the agents under the Equity Distribution Agreements.

No definition available.

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

- Definition

The maximum amount of common limited partners units allowed to issuance under agreement during the period.

+ References

No definition available.

+ Details

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

- Definition

Percentage investment held by members or limited partners of limited liability company (LLC) or limited partnership (LP).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

+ Details

Name:	us-gaap_LimitedLiabilityCompanyLLCOrLimitedPartnershipLPMembersOrLimitedPartnersOwnershipInterest
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
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_LimitedPartnersCapitalAccountLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Total units issued during the year due to the sale of units. All partners include general, limited and preferred partners.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

+ Details

Name:	us-gaap_PartnersCapitalAccountUnitsSaleOfUnits
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The cash inflow from the issuance of common limited partners units during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585

+ Details

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

- Details

Name:	us-gaap_TransactionTypeAxis=bpl_EquityDistributionAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

PARTNERS' CAPITAL AND DISTRIBUTIONS - Narrative (Details) - USD ($) shares in Thousands		1 Months Ended	9 Months Ended
	Sep. 21, 2017	Mar. 31, 2016	Sep. 30, 2017
Partner's capital and distributions
Limited partner ownership percentage			66.67%
Equity Distribution Agreements
Partner's capital and distributions
LP Units authorized to sell (in shares)		$ 500,000,000.0
Proceeds from issuance of units			$ 346,000,000
Compensation fees paid			$ 1,900,000
Limited Partners \| Equity Distribution Agreements
Partner's capital and distributions
Public offering, LP units issued (in shares)	3,800		6,159