Document and Entity Information	9 Months Ended
Sep. 30, 2011	Nov. 02, 2011
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2011
Document Fiscal Year Focus	2011
Document Fiscal Period Focus	Q3
Entity Registrant Name	Piedmont Office Realty Trust, Inc.
Entity Central Index Key	0001042776
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		172,826,991

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