Consolidated Balance Sheets Parenthetical	Dec. 31, 2011	May 31, 2011	Dec. 31, 2010
Equity:
Limited Partner Equity, units issued	86,708,914		85,865,619
Limited Partner Equity, units outstanding	85,571,714		84,728,419
Units issued as a unit distribution		843,295
Treasury Units at Cost, units outstanding	1,137,200		1,137,200

Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

No definition available.

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