Property Dispositions, Assets Held for Sale and Discontinued Operations (Property Dispositions) (Details) - USD ($) $ in Thousands																					12 Months Ended
		Dec. 29, 2016	Dec. 22, 2016	Sep. 28, 2016	Jul. 29, 2016	Jul. 27, 2016	May 02, 2016	Apr. 28, 2016	Apr. 21, 2016	Dec. 21, 2015	Oct. 29, 2015	Sep. 01, 2015	Aug. 10, 2015	Jul. 28, 2015	May 01, 2015	Apr. 29, 2015	Apr. 28, 2015	Jan. 30, 2015	May 29, 2014	May 19, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net Sales Proceeds																					$ 365,918	$ 848,169	$ 46,232
Notes receivable																					$ 0	$ 45,400
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | 2020 W. 89th Street [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revised (2014) or Restated Gain/(Loss) on Sale																				$ 870
Net Sales Proceeds																				$ 5,515
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | Two Park Center [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revised (2014) or Restated Gain/(Loss) on Sale	[1]																		$ (169)
Net Sales Proceeds	[1]																		$ 6,017
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | 3900 Dallas Parkway [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revised (2014) or Restated Gain/(Loss) on Sale																		$ 8,940
Net Sales Proceeds																		$ 25,803
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | 5601 Headquarters Drive [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revised (2014) or Restated Gain/(Loss) on Sale																	$ 6,390
Net Sales Proceeds																	$ 33,326
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | River Corporate Center [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revised (2014) or Restated Gain/(Loss) on Sale																$ 4,144
Net Sales Proceeds																$ 24,223
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | Copper Ridge Center [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revised (2014) or Restated Gain/(Loss) on Sale															$ 11,358
Net Sales Proceeds	[2]														50,372
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | Copper Ridge Center [Member] | Notes Receivable [Member] | Secured Promissory Note [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Notes receivable															$ 45,400
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | Eastpoint I & II [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revised (2014) or Restated Gain/(Loss) on Sale	[3]													$ (177)
Net Sales Proceeds														$ 17,342
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | 3750 Brookside Parkway [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revised (2014) or Restated Gain/(Loss) on Sale													$ 761
Net Sales Proceeds													$ 13,624
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | Chandler Forum [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revised (2014) or Restated Gain/(Loss) on Sale												$ 13,805
Net Sales Proceeds												$ 32,267
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | Aon Center [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revised (2014) or Restated Gain/(Loss) on Sale											$ 84,218
Net Sales Proceeds											$ 646,243
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | 2 Gatehall Drive [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revised (2014) or Restated Gain/(Loss) on Sale	[3]									$ 162
Net Sales Proceeds										$ 50,369
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | 1055 East Colorado [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revised (2014) or Restated Gain/(Loss) on Sale									$ 29,462
Net Sales Proceeds									$ 60,076
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | Fairway Center II [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revised (2014) or Restated Gain/(Loss) on Sale								$ 14,406
Net Sales Proceeds								$ 33,062
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | 1901 Main Street [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revised (2014) or Restated Gain/(Loss) on Sale							$ 29,964
Net Sales Proceeds	[4]						63,149
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | 1901 Main Street [Member] | Notes Receivable [Member] | Secured Promissory Note [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Notes receivable							$ 33,000
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | 9221 Corporate Boulevard [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revised (2014) or Restated Gain/(Loss) on Sale	[3]					$ (192)
Net Sales Proceeds						$ 12,035
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | 150 West Jefferson [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revised (2014) or Restated Gain/(Loss) on Sale	[3]				$ (664)
Net Sales Proceeds					$ 77,844
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | 9200 and 9211 Corporate Boulevard [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revised (2014) or Restated Gain/(Loss) on Sale	[3]			$ (41)
Net Sales Proceeds				$ 12,519
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | 11695 Johns Creek Parkway [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revised (2014) or Restated Gain/(Loss) on Sale			$ 1,978
Net Sales Proceeds			$ 13,827
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | Braker Pointe III [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revised (2014) or Restated Gain/(Loss) on Sale		$ 18,579
Net Sales Proceeds		$ 48,006

[1] Property was owned as part of the unconsolidated joint venture, Fund XIII and REIT Joint Venture. As such, the loss on sale was presented as equity in income/(loss) of unconsolidated joint ventures.

[2] As part of the transaction, Piedmont accepted a secured promissory note from the buyer for the remaining $45.4 million owed on the sale. During the year ended December 31, 2016, the note receivable was repaid in full and such proceeds are reflected in the accompanying consolidated statements of cash flows as net sales proceeds from the sale of wholly-owned properties.

[3] As discussed in Note 10 above, Piedmont recognized an impairment loss prior to, or in conjunction with, the sale of the property. Therefore, any gain/(loss) recognized upon the consummation of the sale consists solely of adjustments made subsequent to the sale for closing cost estimates or post-closing prorations.

[4] As part of the transaction, Piedmont accepted a secured promissory note from the buyer for $33.0 million, and the note receivable was repaid in full during the year ended December 31, 2016. As such, the full proceeds from the sale of the property are reflected in the accompanying consolidated statements of cash flows as net sales proceeds from the sale of wholly-owned properties.