EARNINGS PER UNIT (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
EARNINGS PER UNIT
Net income (loss) attributable to Buckeye Partners, L.P.	$ 111,611us-gaap_IncomeLossAttributableToParent	$ 90,468us-gaap_IncomeLossAttributableToParent
Basic:
Weighted average units outstanding - basic	127,175	115,319
Earnings per unit - basic	$ 0.88	$ 0.78
Diluted:
Weighted average units outstanding - basic	127,175	115,319
Dilutive effect of LP Unit options and LTIP awards granted	432	477
Weighted average units outstanding - diluted	127,607	115,796
Earnings per unit - diluted	$ 0.87	$ 0.78

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- Definition

The portion of profit or loss for the period which is attributable to the parent.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.20)

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187171-122770

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 4

-Section F

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Per unit of ownership amount after tax of income (loss) available to outstanding limited partnership (LP) unit-holder.

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Weighted average number of limited partnership units outstanding determined by relating the portion of time within a reporting period that limited partnership units have been outstanding to the total time in that period.

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The sum of dilutive potential limited partnership units used in the calculation of the diluted per-unit computation.

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