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Basis of Presentation (Details)	6 Months Ended	12 Months Ended
	Jun. 30, 2012	Dec. 31, 2011
Basis of Presentation (Textual) [Abstract]
Percentage of comparable consolidated amounts	99.00%	99.00%

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- Definition

Percentage of comparable asset and revenue consolidated amounts.

+ References

No definition available.

+ Details

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