Organization (Details) ft² in Millions	9 Months Ended
Sep. 30, 2020 ft² property subsidiary segment	Feb. 12, 2020
Segment Reporting, Other Significant Reconciling Item [Line Items]
Number of major U.S. office markets	7
Number of wholly-owned subsidiaries \| subsidiary	2
Number of real estate properties	57
Area of real estate property (in sq ft) \| ft²	17.2
Percentage leased	86.90%	95.00%
Number of operating segments \| segment	1
Piedmont Office Realty Trust, Inc.
Segment Reporting, Other Significant Reconciling Item [Line Items]
Percentage ownership by sole general partner	99.90%
Piedmont Office Holdings, Inc.
Segment Reporting, Other Significant Reconciling Item [Line Items]
Percentage ownership by sole limited partner	0.10%

Number Of Wholly Owned Management Subsidiaries

No definition available.

Name:	pdm_NumberOfWhollyOwnedManagementSubsidiaries
Namespace Prefix:	pdm_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Real Estate Investments, Number of Office Markets

+ References

No definition available.

+ Details

Name:	pdm_RealEstateInvestmentsNumberofOfficeMarkets
Namespace Prefix:	pdm_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage of Leased Real Estate Properties

+ References

No definition available.

+ Details

Name:	pdm_RealEstatePropertyPercentofPropertyUnderLease
Namespace Prefix:	pdm_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Area of a real estate property.

+ References

No definition available.

+ Details

Name:	us-gaap_AreaOfRealEstateProperty
Namespace Prefix:	us-gaap_
Data Type:	num:areaItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage investment held by the managing member or general partner of the limited liability company (LLC) or limited partnership (LP).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

+ Details

Name:	us-gaap_LimitedLiabilityCompanyLLCOrLimitedPartnershipLPManagingMemberOrGeneralPartnerOwnershipInterest
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage investment held by members or limited partners of limited liability company (LLC) or limited partnership (LP).

+ References

+ Details

Name:	us-gaap_LimitedLiabilityCompanyLLCOrLimitedPartnershipLPMembersOrLimitedPartnersOwnershipInterest
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

No definition available.

+ Details

Name:	us-gaap_NumberOfOperatingSegments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of real estate properties owned as of the balance sheet date.

+ References

No definition available.

+ Details

Name:	us-gaap_NumberOfRealEstateProperties
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_SegmentReportingOtherSignificantReconcilingItemLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	srt_OwnershipAxis=pdm_PiedmontOfficeRealtyTrustIncMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_OwnershipAxis=pdm_PiedmontOfficeHoldingsIncMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: