Condensed Statements Of Income (Parenthetical)	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011
Condensed Statements Of Income[Abstract]
Interests outstanding	46,280.3	46,280.3

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

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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 4

-Section F

Reference 2: 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=6959260&loc=d3e187171-122770

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