Summary of Significant Accounting Policies	3 Months Ended
Mar. 31, 2014
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Basis of Presentation and Principles of Consolidation The consolidated financial statements of Piedmont have been prepared in accordance with the rules and regulations of the Securities and Exchange Commission (the “SEC”), including the instructions to Form 10-Q and Article 10 of Regulation S-X, and do not include all of the information and footnotes required by U.S. generally accepted accounting principles (“GAAP”) for complete financial statements. In the opinion of management, the statements for the unaudited interim periods presented include all adjustments, which are of a normal and recurring nature, necessary for a fair presentation of the results for such periods. Results for these interim periods are not necessarily indicative of a full year’s results and certain prior period amounts have been reclassified to conform to the current period financial statement presentation. The reclassifications relate to the required presentation of income from discontinued operations for properties sold during the three months ended March 31, 2014 and during the year ended December 31, 2013 (see Note 8), as well as reclassifying deferred common area maintenance costs from deferred lease costs to prepaid and other assets. None of these reclassifications affect net equity or net income attributable to Piedmont as presented in previous periods. Piedmont’s consolidated financial statements include the accounts of Piedmont, Piedmont’s wholly-owned subsidiaries, any variable interest entity of which Piedmont or any of its wholly-owned subsidiaries is considered the primary beneficiary, or any entity in which Piedmont or any of its wholly-owned subsidiaries owns a controlling interest. For further information, refer to the financial statements and footnotes included in Piedmont’s Annual Report on Form 10-K for the year ended December 31, 2013. All inter-company balances and transactions have been eliminated upon consolidation. Further, Piedmont has formed special purpose entities to acquire and hold real estate. Each special purpose entity is a separate legal entity and consequently the assets of the special purpose entities are not available to all creditors of Piedmont. The assets owned by these special purpose entities are being reported on a consolidated basis with Piedmont’s assets for financial reporting purposes only. Use of Estimates The preparation of the accompanying consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the accompanying consolidated financial statements and notes. Actual results could differ from those estimates. Deferred Financing Costs Costs incurred in connection with obtaining financing which are paid to service providers other than the lenders, or customary fees paid to lenders which are not calculated based on the total commitment of the facility, are capitalized as deferred financing costs in the accompanying consolidated balance sheets. These costs are amortized to interest expense on a straight-line basis (which approximates the effective interest rate method) over the terms of the related financing arrangements. Income Taxes Piedmont has elected to be taxed as a REIT under the Internal Revenue Code of 1986, as amended (the “Code”), and has operated as such, beginning with its taxable year ended December 31, 1998. To qualify as a REIT, Piedmont must meet certain organizational and operational requirements, including a requirement to distribute at least 90% of its annual REIT taxable income. As a REIT, Piedmont is generally not subject to federal income taxes. Piedmont is subject to certain taxes related to the operations of properties in certain locations, as well as operations conducted by its taxable REIT subsidiary, POH, which have been provided for in the financial statements. Recent Accounting Pronouncements The Financial Accounting Standards Board has issued Accounting Standards Update No. 2014-08, Presentation of Financial Statements (Topic 205) and Property, Plant, and Equipment (Topic 360): Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity ("ASU 2014-08"). The amendments in ASU 2014-08 change the criteria for the transactions that qualify to be reported as discontinued operations, and enhance disclosures for transactions which meet the new criteria in this area. Under this new guidance, disposals representing a strategic shift that has (or will have) a major effect on operations should be presented as discontinued operations. The amendments in ASU 2014-08 are effective in the first quarter of 2015 for Piedmont, and early adoption is permitted. Piedmont is currently evaluating the amendments of ASU 2014-08; however, these amendments are expected to impact Piedmont's determination of which future property disposals qualify as discontinued operations, as well as requiring additional disclosures about discontinued operations.

Summary of Significant Accounting Policies

Basis of Presentation and Principles of Consolidation

The consolidated financial statements of Piedmont have been prepared in accordance with the rules and regulations of the Securities and Exchange Commission (the “SEC”), including the instructions to Form 10-Q and Article 10 of Regulation S-X, and do not include all of the information and footnotes required by U.S. generally accepted accounting principles (“GAAP”) for complete financial statements. In the opinion of management, the statements for the unaudited interim periods presented include all adjustments, which are of a normal and recurring nature, necessary for a fair presentation of the results for such periods. Results for these interim periods are not necessarily indicative of a full year’s results and certain prior period amounts have been reclassified to conform to the current period financial statement presentation. The reclassifications relate to the required presentation of income from discontinued operations for properties sold during the three months ended March 31, 2014 and during the year ended December 31, 2013 (see Note 8), as well as reclassifying deferred common area maintenance costs from deferred lease costs to prepaid and other assets. None of these reclassifications affect net equity or net income attributable to Piedmont as presented in previous periods.

Piedmont’s consolidated financial statements include the accounts of Piedmont, Piedmont’s wholly-owned subsidiaries, any variable interest entity of which Piedmont or any of its wholly-owned subsidiaries is considered the primary beneficiary, or any entity in which Piedmont or any of its wholly-owned subsidiaries owns a controlling interest. For further information, refer to the financial statements and footnotes included in Piedmont’s Annual Report on Form 10-K for the year ended December 31, 2013.

All inter-company balances and transactions have been eliminated upon consolidation.

Further, Piedmont has formed special purpose entities to acquire and hold real estate. Each special purpose entity is a separate legal entity and consequently the assets of the special purpose entities are not available to all creditors of Piedmont. The assets owned by these special purpose entities are being reported on a consolidated basis with Piedmont’s assets for financial reporting purposes only.

Use of Estimates

The preparation of the accompanying consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the accompanying consolidated financial statements and notes. Actual results could differ from those estimates.

Deferred Financing Costs

Costs incurred in connection with obtaining financing which are paid to service providers other than the lenders, or customary fees paid to lenders which are not calculated based on the total commitment of the facility, are capitalized as deferred financing costs in the accompanying consolidated balance sheets. These costs are amortized to interest expense on a straight-line basis (which approximates the effective interest rate method) over the terms of the related financing arrangements.

Income Taxes

Piedmont has elected to be taxed as a REIT under the Internal Revenue Code of 1986, as amended (the “Code”), and has operated as such, beginning with its taxable year ended December 31, 1998. To qualify as a REIT, Piedmont must meet certain organizational and operational requirements, including a requirement to distribute at least 90% of its annual REIT taxable income. As a REIT, Piedmont is generally not subject to federal income taxes. Piedmont is subject to certain taxes related to the operations of properties in certain locations, as well as operations conducted by its taxable REIT subsidiary, POH, which have been provided for in the financial statements.

Recent Accounting Pronouncements

The Financial Accounting Standards Board has issued Accounting Standards Update No. 2014-08, Presentation of Financial Statements (Topic 205) and Property, Plant, and Equipment (Topic 360): Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity ("ASU 2014-08"). The amendments in ASU 2014-08 change the criteria for the transactions that qualify to be reported as discontinued operations, and enhance disclosures for transactions which meet the new criteria in this area. Under this new guidance, disposals representing a strategic shift that has (or will have) a major effect on operations should be presented as discontinued operations. The amendments in ASU 2014-08 are effective in the first quarter of 2015 for Piedmont, and early adoption is permitted. Piedmont is currently evaluating the amendments of ASU 2014-08; however, these amendments are expected to impact Piedmont's determination of which future property disposals qualify as discontinued operations, as well as requiring additional disclosures about discontinued operations.