Piedmont Office Realty Trust (PDM) 10-Q 1 Nov 16 2016 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2016	Oct. 31, 2016
Document and Entity Information [Abstract]
Entity Registrant Name	Piedmont Office Realty Trust, Inc.
Entity Central Index Key	1,042,776
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Sep. 30, 2016
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Common Stock, Shares Outstanding		145,235,313

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Assets:
Land	$ 663,697	$ 676,091
Buildings and improvements, less accumulated depreciation of $931,699 and $889,857 as of September 30, 2016 and December 31, 2015, respectively	2,897,639	2,837,463
Intangible lease assets, less accumulated amortization of $102,137 and $93,012 as of September 30, 2016 and December 31, 2015, respectively	92,356	84,663
Construction in progress	35,086	20,975
Real estate assets held for sale, net	0	76,614
Total real estate assets	3,688,778	3,695,806
Investments in and amounts due from unconsolidated joint ventures	7,351	7,577
Cash and cash equivalents	6,032	5,441
Tenant receivables, net of allowance for doubtful accounts of $305 and $83 as of September 30, 2016 and December 31, 2015, respectively	24,785	26,339
Straight-line rent receivables	158,811	147,393
Note receivable	0	45,400
Restricted cash and escrows	5,182	5,174
Prepaid expenses and other assets	28,744	24,777
Goodwill	180,097	180,097
Deferred lease costs, less accumulated amortization of $166,028 and $146,700 as of September 30, 2016 and December 31, 2015, respectively	288,517	288,041
Other assets held for sale, net	0	8,490
Total assets	4,388,297	4,434,535
Liabilities:
Unsecured debt, net of discount and unamortized debt issuance costs of $10,934 and $12,779 as of September 30, 2016 and December 31, 2015, respectively	1,661,066	1,528,221
Secured debt, net of premiums and unamortized debt issuance costs of $1,210 and $1,319 as of September 30, 2016 and December 31, 2015, respectively	333,012	501,289
Accounts payable, accrued expenses, and accrued capital expenditures	133,112	128,465
Deferred income	29,006	27,270
Intangible lease liabilities, less accumulated amortization of $47,067 and $42,315 as of September 30, 2016 and December 31, 2015, respectively	45,283	42,853
Interest rate swaps	17,835	9,993
Total liabilities	2,219,314	2,238,091
Commitments and Contingencies	0	0
Stockholders’ Equity:
Shares-in-trust, 150,000,000 shares authorized; none outstanding as of September 30, 2016 or December 31, 2015	0	0
Preferred stock, no par value, 100,000,000 shares authorized; none outstanding as of September 30, 2016 or December 31, 2015	0	0
Common stock, $.01 par value, 750,000,000 shares authorized; 145,233,753 and 145,511,644 shares issued and outstanding as of September 30, 2016 and December 31, 2015, respectively	1,452	1,455
Additional paid-in capital	3,672,218	3,669,977
Cumulative distributions in excess of earnings	(1,499,374)	(1,477,674)
Other comprehensive income/(loss)	(7,211)	1,661
Piedmont stockholders’ equity	2,167,085	2,195,419
Noncontrolling interest	1,898	1,025
Total stockholders’ equity	2,168,983	2,196,444
Total liabilities and stockholders’ equity	$ 4,388,297	$ 4,434,535

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands		Sep. 30, 2016	Dec. 31, 2015
Assets:
Intangible lease assets, accumulated amortization		$ 102,137	$ 93,012
Tenant receivables, allowance for doubtful accounts		305	83
Deferred lease costs, accumulated amortization		166,028	146,700
Liabilities:
Intangible lease liabilities, accumulated amortization		$ 47,067	$ 42,315
Stockholders’ Equity:
Shares-in-trust, shares authorized		150,000,000	150,000,000
Shares-in-trust, shares outstanding		0	0
Preferred stock, par value (in dollars per share)		$ 0	$ 0
Preferred stock, shares authorized		100,000,000	100,000,000
Preferred stock, shares outstanding		0	0
Common stock, par value (in dollars per share)		$ 0.01	$ 0.01
Common stock, shares authorized		750,000,000	750,000,000
Common stock, shares issued		145,233,753	145,511,644
Common stock, shares outstanding		145,233,753	145,511,644
Unsecured Debt [Member]
Liabilities:
Discount, (premiums) and unamortized debt issuance costs	[1]	$ 10,934	$ 12,779
Secured Debt [Member]
Liabilities:
Discount, (premiums) and unamortized debt issuance costs	[1]	(1,210)	(1,319)
Building and improvements Member]
Assets:
Buildings and improvements, accumulated depreciation		$ 931,699	$ 889,857
[1]	Other than the $35 Million Fixed-Rate Loan, all of Piedmont’s outstanding debt as of September 30, 2016 and December 31, 2015 is interest-only.

Consolidated Statements of Inco

Consolidated Statements of Income - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Revenues:
Rental income		$ 113,821	$ 117,994	$ 340,326	$ 353,255
Tenant reimbursements		24,163	30,273	70,000	90,476
Property management fee revenue		501	548	1,478	1,577
Total revenues		138,485	148,815	411,804	445,308
Expenses:
Property operating costs		54,867	61,653	161,438	187,368
Depreciation		31,610	31,199	94,948	103,470
Amortization		18,640	14,021	53,848	43,646
Impairment loss on real estate assets	[1]	22,590	34,815	30,898	40,169
General and administrative		7,429	8,260	23,518	22,750
Operating expenses		135,136	149,948	364,650	397,403
Real estate operating income/(loss)		3,349	(1,133)	47,154	47,905
Other income (expense):
Interest expense		(15,496)	(18,832)	(48,294)	(56,020)
Other income/(expense)		(720)	803	(467)	1,218
Recovery from casualty event		34	0	34	0
Equity in income of unconsolidated joint ventures		128	135	354	418
Other income (expense)		(16,054)	(17,894)	(48,373)	(54,384)
Loss from continuing operations		(12,705)	(19,027)	(1,219)	(6,479)
Discontinued operations:
Operating income		1	16	0	13
Loss on sale of real estate assets		0	(2)	0	(2)
Income from discontinued operations		1	14	0	11
Gain/(loss) on sale of real estate assets		(57)	17,142	78,910	53,826
Net income/(loss)		(12,761)	(1,871)	77,691	47,358
Less: Net loss/(income) applicable to noncontrolling interest		15	(4)	7	(12)
Net income/(loss) applicable to Piedmont		$ (12,746)	$ (1,875)	$ 77,698	$ 47,346
Per share information – basic and diluted:
Income/(loss) from continuing operations and gain on sale of real estate assets (in dollars per share)		$ (0.09)	$ (0.01)	$ 0.53	$ 0.31
Net income/ (loss) applicable to common stockholders (in dollars per share)		$ (0.09)	$ (0.01)	$ 0.53	$ 0.31
Weighted-average common shares outstanding – basic		145,231,160	148,855,336	145,228,755	152,231,060
Weighted-average common shares outstanding – diluted	[2]	145,669,237	149,176,207	145,601,026	152,499,430
[1]	The fair value measurements used in the evaluation of the non-financial assets above are considered to be Level 1 valuations within the fair value hierarchy as defined by GAAP, as there are direct observations and transactions involving the assets by unrelated, third-party purchasers.
[2]	Due to repurchases of common stock during the current year, Piedmont has 145,233,753 shares of common stock outstanding as of September 30, 2016.

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Statement of Comprehensive Income [Abstract]
Net income applicable to Piedmont	$ (12,746)	$ (1,875)	$ 77,698	$ 47,346
Other comprehensive income/(loss):
Effective portion of gain/(loss) on derivative instruments that are designated and qualify as cash flow hedges (See Note 6)	2,847	(22,263)	(12,182)	(21,389)
Plus: Reclassification of previously recorded loss included in net income (See Note 6)	1,045	1,506	3,291	4,575
Gain/(loss) on investment in available for sale securities	7	(9)	19	(11)
Other comprehensive income/(loss)	3,899	(20,766)	(8,872)	(16,825)
Comprehensive income/(loss) applicable to Piedmont	$ (8,847)	$ (22,641)	$ 68,826	$ 30,521

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Cumulative Distributions in Excess of Earnings [Member]	Other Comprehensive Income/ (Loss) [Member]	Non-controlling Interest [Member]
Balance at Dec. 31, 2014	$ 2,312,015	$ 1,543	$ 3,666,182	$ (1,365,620)	$ 8,301	$ 1,609
Balance (in shares) at Dec. 31, 2014		154,324,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share repurchases as part of an announced plan	(158,860)	$ (90)		(158,770)
Share repurchases as part of an announced plan, shares		(8,980,000)
Offering costs	(326)		(326)
Redemption of noncontrolling interest in consolidated variable interest entity	54		54
Reallocation of noncontrolling interest of subsidiary	544		1,128			(584)
Dividends to common stockholders ($0.84 (YTD 2015) and $0.63 (YTD 2016) per share), dividends to stockholders of subsidiary, and dividends reinvested	(126,531)		(242)	(126,274)		(15)
Shares issued and amortized under the 2007 Omnibus Incentive Plan, net of tax	3,183	$ 2	3,181
Shares issued and amortized under the 2007 Omnibus Incentive Plan, net of tax (in shares)		168,000
Net income (loss) applicable to noncontrolling interest	15					15
Net income applicable to Piedmont	172,990			172,990
Other comprehensive loss	(6,640)				(6,640)
Balance at Dec. 31, 2015	$ 2,196,444	$ 1,455	3,669,977	(1,477,674)	1,661	1,025
Balance (in shares) at Dec. 31, 2015	145,511,644	145,512,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share repurchases as part of an announced plan	$ (7,943)	$ (5)		(7,938)
Share repurchases as part of an announced plan, shares		(462,000)
Offering costs	(239)		(239)
Non-controlling interest in consolidated joint venture	888					888
Dividends to common stockholders ($0.84 (YTD 2015) and $0.63 (YTD 2016) per share), dividends to stockholders of subsidiary, and dividends reinvested	(91,609)		(141)	(91,460)		(8)
Shares issued and amortized under the 2007 Omnibus Incentive Plan, net of tax	2,623	$ 2	2,621
Shares issued and amortized under the 2007 Omnibus Incentive Plan, net of tax (in shares)		184,000
Net income (loss) applicable to noncontrolling interest	(7)					(7)
Net income applicable to Piedmont	77,698			77,698
Other comprehensive loss	(8,872)				(8,872)
Balance at Sep. 30, 2016	$ 2,168,983	$ 1,452	$ 3,672,218	$ (1,499,374)	$ (7,211)	$ 1,898
Balance (in shares) at Sep. 30, 2016	145,233,753	145,234,000

Consolidated Statements of Sto7

Consolidated Statements of Stockholders' Equity (Unaudited) (Parenthetical) - $ / shares	9 Months Ended	12 Months Ended
	Sep. 30, 2016	Dec. 31, 2015
Statement of Stockholders' Equity [Abstract]
Dividends to common stockholders per share	$ 0.63	$ 0.84

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands		9 Months Ended
		Sep. 30, 2016	Sep. 30, 2015
Cash Flows from Operating Activities:
Net income		$ 77,691	$ 47,358
Operating distributions received from unconsolidated joint ventures		579	565
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation		94,948	103,470
Amortization of debt issuance costs		1,264	1,281
Loss on settlement of forward starting interest rate swaps		0	(1,284)
Other amortization		53,325	44,091
Impairment loss on real estate assets	[1]	30,898	40,169
Stock compensation expense		7,630	6,692
Equity in income of unconsolidated joint ventures		(354)	(418)
Gain on sale of real estate assets, net		(78,910)	(53,824)
Changes in assets and liabilities:
Increase in tenant and straight-line rent receivables, net		(17,393)	(22,996)
Decrease/(increase) in restricted cash and escrows		3,451	(20,333)
Increase in prepaid expenses and other assets		(3,429)	(5,845)
Increase/(decrease) in accounts payable and accrued expenses		307	(8,284)
Increase in deferred income		2,029	3,619
Net cash provided by operating activities		172,036	134,261
Cash Flows from Investing Activities:
Acquisition of real estate assets and related intangibles		(66,900)	(75,976)
Capitalized expenditures, net of accruals		(88,391)	(81,917)
Investment in consolidated joint venture		(165,848)	0
Redemption of noncontrolling interest in unconsolidated variable interest entity		0	(4,000)
Net sales proceeds from wholly-owned properties		304,902	151,564
Deferred lease costs paid		(15,345)	(23,889)
Net cash used in investing activities		(31,582)	(34,218)
Cash Flows from Financing Activities:
Debt issuance costs paid		(212)	(1,048)
Proceeds from debt		552,000	1,205,857
Repayments of debt		(589,532)	(1,055,902)
Costs of issuance of common stock		(239)	(326)
Shares withheld to pay tax obligations related to employee stock compensation		(2,328)	(1,665)
Repurchases of common stock as part of announced plan		(7,943)	(155,653)
Dividends paid and discount on dividend reinvestments		(91,609)	(95,910)
Net cash used in financing activities		(139,863)	(104,647)
Net increase/(decrease) in cash and cash equivalents		591	(4,604)
Cash and cash equivalents, beginning of period		5,441	12,306
Cash and cash equivalents, end of period		6,032	7,702
Supplemental Disclosures of Significant Noncash Investing and Financing Activities:
Change in accrued share repurchases as part of an announced plan		0	(822)
Accrued capital expenditures and deferred lease costs		$ 24,624	$ 24,588
[1]	The fair value measurements used in the evaluation of the non-financial assets above are considered to be Level 1 valuations within the fair value hierarchy as defined by GAAP, as there are direct observations and transactions involving the assets by unrelated, third-party purchasers.

Organization

Organization	9 Months Ended
	Sep. 30, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization	Organization Piedmont Office Realty Trust, Inc. (“Piedmont”) (NYSE: PDM) is a Maryland corporation that operates in a manner so as to qualify as a real estate investment trust (“REIT”) for federal income tax purposes and engages in the acquisition, development, management, and ownership of commercial real estate properties throughout the United States, including properties that are under construction, are newly constructed, or have operating histories. Piedmont was incorporated in 1997 and commenced operations in 1998. Piedmont conducts business primarily through Piedmont Operating Partnership, L.P. (“Piedmont OP”), a Delaware limited partnership, as well as performing the management of its buildings through two wholly-owned subsidiaries, Piedmont Government Services, LLC and Piedmont Office Management, LLC. Piedmont owns 99.9% of, and is the sole general partner of, Piedmont OP and as such, possesses full legal control and authority over the operations of Piedmont OP. The remaining 0.1% ownership interest of Piedmont OP is held indirectly by Piedmont through its wholly-owned subsidiary, Piedmont Office Holdings, Inc. ("POH"), the sole limited partner of Piedmont OP. Piedmont OP owns properties directly, through wholly-owned subsidiaries, and through both consolidated and unconsolidated joint ventures. References to Piedmont herein shall include Piedmont and all of its subsidiaries, including Piedmont OP and its subsidiaries and joint ventures. As of September 30, 2016 , Piedmont owned 65 office properties, one redevelopment asset, two development assets, and one building through an unconsolidated joint venture. Piedmont's 65 office properties comprise 18.4 million square feet of primarily Class A commercial office space, and were 93.4% leased as of September 30, 2016 . As of September 30, 2016 , approximately 87% of Piedmont's Annualized Lease Revenue was generated from select office sub-markets in the following cities: Atlanta, Boston, Chicago, Dallas, Minneapolis, New York, Orlando, and Washington, D.C. Piedmont internally evaluates all of its real estate assets as one operating segment, and accordingly, does not report segment information.

Summary of Significant Accounti

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2016
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. Piedmont’s consolidated financial statements include the accounts of Piedmont, Piedmont’s wholly-owned subsidiaries, any variable interest entity ("VIE") of which Piedmont or any of its wholly-owned subsidiaries is considered to have the power to direct the activities of the entity and the obligation to absorb losses/right to receive benefits, or any entity in which Piedmont or any of its wholly-owned subsidiaries owns a controlling interest. In determining whether Piedmont or Piedmont OP has a controlling interest, the following factors, among others, are considered: equity ownership, voting rights, protective rights of investors, and participatory rights of investors. 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, 2015 . 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. Consequently, the assets of these 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. Income Taxes Piedmont has elected to be taxed as a REIT under the Internal Revenue Code of 1986, as amended, 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, subject to fulfilling, among other things, this distribution requirement. 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. Tenant Receivables, net and Straight-line Rent Receivables Tenant receivables are comprised of rental and reimbursement billings due from tenants, and straight-line rent receivables representing the cumulative amount of future adjustments necessary to present rental income on a straight-line basis. Tenant receivables are recorded at the original amount earned, less an allowance for any doubtful accounts, which approximates estimated fair value. Management assesses the collectibility of tenant receivables on an ongoing basis and provides for allowances as such balances, or portions thereof, become uncollectible. Effective July 1, 2016, Piedmont began classifying provisions for bad debts as nonrecoverable property operating costs in the accompanying consolidated statements of income to include such expenses as a component of operating the underlying properties. Previously, such costs were presented as general and administrative expenses. In order to conform with the presentation used during the three months ended September 30, 2016, Piedmont reclassified approximately $100,000 of provisions for/(recoveries of) bad debts for the nine months ended September 30, 2016, and approximately $(20,000) for the three and nine months ended September 30, 2015. Further, Piedmont recognized approximately $190,000 of provisions for bad debts during the three months ended September 30, 2016 as a component of nonrecoverable property operating costs. Accounting Pronouncements Adopted during the Nine Months Ended September 30, 2016 As of January 1, 2016, Piedmont early adopted the provisions of Financial Accounting Standards Board (the "FASB") Accounting Standards Update No. 2016-09, Compensation- Stock Compensation (Topic 718) Improvements to Employee Share-Based Payment Accounting ("ASU 2016-09"). The provisions in ASU 2016-09 simplify the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities, and classification on the statement of cash flows. The implementation of ASU 2016-09 resulted in the reclassification of approximately $1.7 million related to income tax consequences for share-based compensation from cash outflows from operating activities to cash outflows from financing activities in the accompanying consolidated statements of cash flows for the nine months ended September 30, 2015. Additionally, as of January 1, 2016, Piedmont also adopted Accounting Standards Update No. 2015-05, Intangibles- Goodwill and Other- Internal-Use Software (Subtopic 350-40) “Customer’s Accounting for Fees Paid in a Cloud Computing Arrangement on a prospective basis. Other Recent Accounting Pronouncements The FASB has issued Accounting Standards Update No. 2016-05, Derivatives and Hedging (Topic 815), Effect of Derivative Contract Novations on Existing Hedge Accounting Relationships ("ASU 2016-05"). The amendments in ASU 2016-05 clarify that a change in the counterparty to a derivative instrument that has been designated as the hedging instrument does not, in and of itself, require de-designation of that hedging relationship provided that all other hedge accounting criteria continue to be met. The amendments in ASU 2016-05 are effective in the first quarter of 2017, and Piedmont does not anticipate any material impact to its consolidated financial statements as a result of adoption. The FASB has issued Accounting Standards Update No. 2014-09, Revenue from Contracts with Customers (Topic 606) ("ASU 2014-09") and Accounting Standards Update No. 2016-08, Revenue from Contracts with Customers (Topic 606) Principal versus Agent Considerations (Reporting Revenue Gross versus Net) ("ASU 2016-08"). The amendments in ASU 2014-09, which are further clarified in ASU 2016-08, as well as ASU 2016-10 and ASU 2016-12, change the criteria for the recognition of revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services using a five-step determination process. Steps 1 through 5 involve (i) identifying contracts with a customer, (ii) identifying the performance obligations in the contract, (iii) determining the transaction price, (iv) allocating the transaction price to the performance obligations, and (v) recognizing revenue as an entity satisfies a performance obligation. Additionally, lease contracts are specifically excluded from ASU 2014-09. The amendments in ASU 2014-09 and ASU 2016-08 are effective in the first quarter of 2018, and Piedmont is currently evaluating the potential impact, if any, of adoption. The FASB has issued Accounting Standards Update No. 2016-01, Financial Instruments - Overall (Subtopic 825-10), Recognition and Measurement of Financial Assets and Financial Liabilities ("ASU 2016-01"). The amendments in ASU 2016-01 require equity investments, except those accounted for under the equity method of accounting, to be measured at estimated fair value with changes in fair value recognized in net income. Additionally, ASU 2016-01 simplifies the impairment assessment of equity investments, and eliminates certain disclosure requirements. The amendments in ASU 2016-01 are effective in the first quarter of 2018, and Piedmont is currently evaluating the potential impact of adoption. The FASB has issued Accounting Standards Update No. 2016-02, Leases (Topic 842), ("ASU 2016-02"). The amendments in ASU 2016-02 fundamentally change the definition of a lease, as well as the accounting for operating leases by requiring leasees to recognize assets and liabilities which arise from the lease, consisting of a liability to make lease payments (the lease liability) and a right-of-use asset, representing the right to use the leased asset over the term of the lease. Accounting for leases for lessors is substantially unchanged from prior practice, which means continuing to recognize lease revenue on a straight-line basis. The amendments in ASU 2016-02 are effective in the first quarter of 2019, and Piedmont is currently evaluating the potential impact of adoption. The FASB has issued Accounting Standards Update No. 2016-13, Financial Instruments—Credit Losses (Topic 326), Measurement of Credit Losses on Financial Instruments ("ASU 2016-13"). The provisions of ASU 2016-13 replace the "incurred loss" approach with an "expected loss" model for impairing trade and other receivables, held-to-maturity debt securities, net investment in leases, and off-balance-sheet credit exposures, which will generally result in earlier recognition of allowance for losses. Additionally, the provisions change the classification of credit losses on available-for-sale securities as an allowance rather than reductions in the amortized cost of the securities. ASU 2016-13 is effective in the first quarter of 2020, with early adoption permitted as of January 1, 2019. Piedmont is currently evaluating the potential impact of adoption. The FASB has issued Accounting Standards Update No. 2016-15, Statement of Cash Flows (Topic 230), Classification of Certain Cash Receipts and Cash Payments ("ASU 2016-15"). The provisions of ASU 2016-15 provide clarity of treatment in the statement of cash flows for several transactions, including debt repayments or debt extinguishment costs, proceeds received from the settlement of insurance claims, and distributions received from equity method investees, among several other topics. The FASB issued ASU 2016-15 in an effort to eliminate diversity in practice regarding treatment of specific transactions in the statements of cash flows for registrants. ASU 2016-15 is effective for Piedmont in the first quarter of 2018, with early adoption permitted. Piedmont is currently evaluating the potential impact of adoption.

Acquisitions

Acquisitions	9 Months Ended
	Sep. 30, 2016
Business Combinations [Abstract]
Acquisitions	Acquisitions During the nine months ended September 30, 2016 , Piedmont acquired one property, as well as a 99% interest in a joint venture owning two properties, using proceeds from the $500 Million Unsecured 2015 Line of Credit, proceeds from the sales of other properties, and cash on hand, as noted below: Property Metropolitan Statistical Area Date of Acquisition Ownership Percentage Acquired Rentable Square Feet (Unaudited) Percentage Leased as of Acquisition (Unaudited) Net Contractual Purchase Price (in millions) CNL Tower I & II Orlando, Florida August 1, 2016 99 % 622,488 95 % $ 166.7 One Wayside Road Boston, Massachusetts August 10, 2016 100 % 200,605 100 % $ 62.9

Debt

Debt	9 Months Ended
	Sep. 30, 2016
Debt Disclosure [Abstract]
Debt	Debt During the nine months ended September 30, 2016 , Piedmont repaid the outstanding balance of its $125 Million Fixed-Rate Loan and its $42.5 Million Fixed-Rate Loan, utilizing the first available prepayment opportunity without penalty. Separately, Piedmont incurred net borrowings on its $500 Million Unsecured 2015 Line of Credit of approximately $131.0 million . As of September 30, 2016 , Piedmont believes it was in compliance with all financial covenants associated with its debt instruments. See Note 7 for a description of Piedmont’s estimated fair value of debt as of September 30, 2016 . Piedmont made interest payments on all debt facilities, including interest rate swap cash settlements, of approximately $18.5 million and $20.1 million for the three months ended September 30, 2016 and 2015 , respectively, and approximately $53.2 million and $58.8 million for the nine months ended September 30, 2016 and 2015 , respectively. Piedmont capitalized interest of approximately $1.5 million and $1.0 million for the three months ended September 30, 2016 and 2015 , respectively, and approximately $3.4 million and $2.7 million for the nine months ended September 30, 2016 and 2015 , respectively. The following table summarizes the terms of Piedmont’s indebtedness outstanding as of September 30, 2016 and December 31, 2015 (in thousands): Facility (1) Stated Rate Effective Rate (2) Maturity Amount Outstanding as of 2016 2015 Secured (Fixed) $125 Million Fixed-Rate Loan 5.50 % 5.50 % 4/1/2016 $ — $ 125,000 $42.5 Million Fixed-Rate Loan 5.70 % 5.70 % 10/11/2016 — 42,525 $140 Million WDC Fixed-Rate Loans (3) 5.76 % 5.76 % 11/1/2017 140,000 140,000 $35 Million Fixed-Rate Loan (4) 5.55 % 3.75 % 9/1/2021 31,802 32,445 $160 Million Fixed-Rate Loan (5) 3.48 % 3.58 % 7/5/2022 160,000 160,000 Net premium and unamortized debt issuance costs 1,210 1,319 Subtotal/Weighted Average (6) 4.64 % 333,012 501,289 Unsecured (Variable and Fixed) $170 Million Unsecured 2015 Term Loan (7) LIBOR + 1.125% 1.66 % 5/15/2018 170,000 170,000 $300 Million Unsecured 2013 Term Loan LIBOR + 1.20% 2.78 % 1/31/2019 300,000 300,000 $500 Million Unsecured 2015 Line of Credit (7) LIBOR + 1.00% 1.53 % 6/18/2019 (8) 152,000 21,000 $300 Million Unsecured 2011 Term Loan (9) LIBOR + 1.15% 2.39 % 1/15/2020 300,000 300,000 $350 Million Senior Notes 3.40 % 3.43 % 6/01/2023 350,000 350,000 $400 Million Senior Notes 4.45 % 4.10 % 3/15/2024 400,000 400,000 Discounts and unamortized debt issuance costs (10,934) (12,779) Subtotal/Weighted Average (6) 3.01 % 1,661,066 1,528,221 Total/Weighted Average (6) 3.28 % $ 1,994,078 $ 2,029,510 (1) Other than the $35 Million Fixed-Rate Loan, all of Piedmont’s outstanding debt as of September 30, 2016 and December 31, 2015 is interest-only. (2) Effective rate after consideration of settled or in place interest rate swap agreements and/or issuance premiums or discounts. (3) Collateralized by the 1201 and 1225 Eye Street buildings in Washington, D.C. (4) Collateralized by the 5 Wall Street building in Burlington, Massachusetts. (5) Collateralized by the 1901 Market Street building in Philadelphia, Pennsylvania. (6) Weighted average is based on contractual balance of outstanding debt and the stated or effectively fixed interest rates in the table as of September 30, 2016 . (7) On a periodic basis, Piedmont may select from multiple interest rate options, including the prime rate and various-length LIBOR locks. All LIBOR selections are subject to an additional spread over the selected rate based on Piedmont’s current credit rating. (8) Piedmont may extend the term for up to one additional year (through two available six month extensions to a final extended maturity date of June 18, 2020) provided Piedmont is not then in default and upon payment of extension fees. (9) The $300 Million Unsecured 2011 Term Loan has a stated variable rate; however, Piedmont has entered into interest rate swap agreements which effectively fix, exclusive of changes to Piedmont's credit rating, the rate on this facility to 2.39% through the original maturity date of November 22, 2016 and 3.35% from November 22, 2016 to January 15, 2020.

Variable Interest Entities

Variable Interest Entities	9 Months Ended
	Sep. 30, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Variable Interest Entities	Variable Interest Entities Variable interest holders who have the power to direct the activities of the VIE that most significantly impact the entity’s economic performance and have the obligation to absorb the majority of losses of the entity or the right to receive significant benefits of the entity must consolidate the VIE. Each of the following VIEs has the sole purpose of holding land and office buildings and their resulting operations, and are classified in the accompanying consolidated balance sheets in the same manner as Piedmont’s wholly-owned properties. A summary of Piedmont’s interests in, and consolidation treatment of, its VIEs and their related carrying values as of September 30, 2016 and December 31, 2015 is as follows (net carrying amount in millions): Entity Piedmont’s % Ownership of Entity Related Building Consolidated/ Unconsolidated Net Carrying Amount as of September 30, 2016 Net Carrying Amount as of December 31, 2015 Primary Beneficiary Considerations 1201 Eye Street N.W. Associates, LLC 49.5% 1201 Eye Street Consolidated $ (7.1 ) $ (7.4 ) In accordance with the partnership’s governing documents, Piedmont is entitled to 100% of the cash flow of the entity and has sole discretion in directing the management and leasing activities of the building. 1225 Eye Street N.W. Associates, LLC 49.5% 1225 Eye Street Consolidated $ 9.9 $ 3.8 In accordance with the partnership’s governing documents, Piedmont is entitled to 100% of the cash flow of the entity and has sole discretion in directing the management and leasing activities of the building. Piedmont 500 W. Monroe Fee, LLC 100% 500 W. Monroe Consolidated $ 263.1 $ 251.4 The Omnibus Agreement with the previous owner includes equity participation rights for the previous owner, if certain financial returns are achieved; however, Piedmont has sole decision making authority and is entitled to 100% of the economic benefits of the property until such returns are met. Piedmont TownPark Land, LLC previously had an equity participation rights agreement outstanding; however, during the nine months ended September 30, 2016 , Piedmont exercised its right to terminate the equity participation rights agreement related to Piedmont TownPark Land, LLC, without payment of any consideration.

Derivative Instruments

Derivative Instruments	9 Months Ended
	Sep. 30, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments	Derivative Instruments Risk Management Objective of Using Derivatives In addition to operational risks which arise in the normal course of business, Piedmont is exposed to economic risks such as interest rate, liquidity, and credit risk. In certain situations, Piedmont has entered into derivative financial instruments such as interest rate swap agreements and other similar agreements to manage interest rate risk exposure arising from current or future variable rate debt transactions. Interest rate swap agreements involve the receipt or payment of future known and uncertain cash amounts, the value of which are determined by interest rates. Piedmont’s objective in using interest rate derivatives is to add stability to interest expense and to manage its exposure to interest rate movements. Cash Flow Hedges of Interest Rate Risk Interest rate swaps designated as cash flow hedges involve the receipt of variable-rate amounts from a counterparty in exchange for Piedmont making fixed-rate payments over the life of the agreements without changing the underlying notional amount. As of September 30, 2016 , Piedmont was party to various interest rate swap agreements which fully hedge the variable cash flows associated with its $300 Million Unsecured 2011 Term Loan and its $300 Million Unsecured 2013 Term Loan. Piedmont continues to hold forward starting interest rate swap agreements related to the extension period of the $300 Million Unsecured 2011 Term Loan, and the maximum length of time over which Piedmont is hedging its exposure to the variability in future cash flows for forecasted transactions is 39 months. A detail of Piedmont’s interest rate derivatives outstanding as of September 30, 2016 is as follows: Interest Rate Derivatives: Number of Swap Agreements Associated Debt Instrument Total Notional Amount (in millions) Effective Date Maturity Date Interest rate swaps 4 $300 Million Unsecured 2011 Term Loan $ 300 11/22/2011 11/22/2016 Interest rate swaps 4 $300 Million Unsecured 2013 Term Loan 200 1/30/2014 1/31/2019 Interest rate swaps 2 $300 Million Unsecured 2013 Term Loan 100 8/29/2014 1/31/2019 Forward starting interest rate swaps 3 $300 Million Unsecured 2011 Term Loan 300 11/22/2016 1/15/2020 Total $ 900 Piedmont presents its interest rate derivatives on its consolidated balance sheets on a gross basis as interest rate swap assets and interest rate swap liabilities. A detail of Piedmont’s interest rate derivatives on a gross and net basis as of September 30, 2016 and December 31, 2015 , respectively, is as follows (in thousands): Interest rate swaps classified as: September 30, December 31, Gross derivative assets $ — $ — Gross derivative liabilities 17,835 9,993 Net derivative liability $ 17,835 $ 9,993 All of Piedmont's interest rate derivative agreements outstanding for the periods presented were designated as cash flow hedges of interest rate risk. As such, the effective portion of changes in the estimated fair value of these derivatives is recorded in other comprehensive income ("OCI") and is reclassified into earnings as interest expense in the period that the hedged forecasted transaction affects earnings. In addition, in conjunction with the issuance of various unsecured notes, Piedmont settled various forward starting swap agreements for gains/losses which were recorded as accumulated other comprehensive income and are being amortized as an offset to interest expense over the term of the respective notes on a straight line basis (which approximates the effective interest method). The effective portion of Piedmont's interest rate derivatives, including the gain/(loss) on previously settled forward swaps, that was recorded in the accompanying consolidated statements of income for the three and nine months ended September 30, 2016 and 2015 , respectively, was as follows (in thousands): Three Months Ended Nine Months Ended Interest Rate Swaps in Cash Flow Hedging Relationships September 30, September 30, September 30, September 30, Amount of gain/(loss) recognized in OCI on derivative $ 2,847 $ (22,263 ) $ (12,182 ) $ (21,389 ) Amount of previously recorded loss reclassified from accumulated OCI into interest expense $ 1,045 $ 1,506 $ 3,291 $ 4,575 Piedmont estimates that approximately $5.4 million will be reclassified from accumulated other comprehensive loss to interest expense over the next twelve months. Piedmont recognized no loss related to hedge ineffectiveness and terminations of its cash flow hedges during the three and nine months ended September 30, 2016 and 2015 , respectively. Additionally, see Note 7 for fair value disclosures of Piedmont's derivative instruments. Credit-risk-related Contingent Features Piedmont has agreements with its derivative counterparties that contain a provision whereby if Piedmont defaults on any of its indebtedness, including default where repayment of the indebtedness has not been accelerated by the lender, then Piedmont could also be declared in default on its derivative obligations. If Piedmont were to breach any of the contractual provisions of the derivative contracts, it would be required to settle its obligations under the agreements at their termination value of the estimated fair values plus accrued interest, or approximately $18.2 million as of September 30, 2016 . Additionally, Piedmont has rights of set-off under certain of its derivative agreements related to potential termination fees and amounts payable under the agreements, if a termination were to occur.

Fair Value Measurement of Finan

Fair Value Measurement of Financial Instruments	9 Months Ended
	Sep. 30, 2016
Fair Value Disclosures [Abstract]
Fair Value Measurement of Financial Instruments	Fair Value Measurement of Financial Instruments Piedmont considers its cash and cash equivalents, tenant receivables, notes receivable, restricted cash and escrows, accounts payable and accrued expenses, interest rate swap agreements, and debt to meet the definition of financial instruments. The following table sets forth the carrying and estimated fair value for each of Piedmont’s financial instruments, as well as its level within the GAAP fair value hierarchy, as of September 30, 2016 and December 31, 2015 , respectively (in thousands): September 30, 2016 December 31, 2015 Financial Instrument Carrying Value Estimated Fair Value Level Within Fair Value Hierarchy Carrying Value Estimated Fair Value Level Within Fair Value Hierarchy Assets: Cash and cash equivalents (1) $ 6,032 $ 6,032 Level 1 $ 5,441 $ 5,441 Level 1 Tenant receivables, net (1) $ 24,785 $ 24,785 Level 1 $ 26,339 $ 26,339 Level 1 Notes receivable (1) $ — $ — Level 1 $ 45,400 $ 45,400 Level 1 Restricted cash and escrows (1) $ 5,182 $ 5,182 Level 1 $ 5,174 $ 5,174 Level 1 Liabilities: Accounts payable and accrued expenses (1) $ 17,753 $ 17,753 Level 1 $ 13,188 $ 13,188 Level 1 Interest rate swap liability $ 17,835 $ 17,835 Level 2 $ 9,993 $ 9,993 Level 2 Debt $ 1,994,078 $ 2,039,912 Level 2 $ 2,029,510 $ 2,039,139 Level 2 (1) For the periods presented, the carrying value of these financial instruments approximates estimated fair value due to their short-term maturity. Piedmont's debt was carried at book value as of September 30, 2016 and December 31, 2015 ; however, Piedmont's estimate of its estimated fair value is disclosed in the table above. Piedmont uses widely accepted valuation techniques including discounted cash flow analysis based on the contractual terms of the debt facilities, including the period to maturity of each instrument, and uses observable market-based inputs for similar debt facilities which have transacted recently in the market. Therefore, the estimated fair values determined are considered to be based on significant other observable inputs (Level 2). Scaling adjustments are made to these inputs to make them applicable to the remaining life of Piedmont's outstanding debt. Piedmont has not changed its valuation technique for estimating the fair value of its debt. Piedmont’s interest rate swap and forward starting interest rate swap agreements presented above, and further discussed in Note 6 , are classified as “Interest rate swap” liabilities in the accompanying consolidated balance sheets and were carried at estimated fair value as of September 30, 2016 and December 31, 2015 . The valuation of these derivative instruments was determined using widely accepted valuation techniques including discounted cash flow analysis based on the contractual terms of the derivatives, including the period to maturity of each instrument, and uses observable market-based inputs, including interest rate curves and implied volatilities. Therefore, the estimated fair values determined are considered to be based on significant other observable inputs (Level 2). In addition, Piedmont considered both its own and the respective counterparties’ risk of nonperformance in determining the estimated fair value of its derivative financial instruments by estimating the current and potential future exposure under the derivative financial instruments that both Piedmont and the counterparties were at risk for as of the valuation date. The credit risk of Piedmont and its counterparties was factored into the calculation of the estimated fair value of the interest rate swaps; however, as of September 30, 2016 and December 31, 2015 , this credit valuation adjustment did not comprise a material portion of the estimated fair value. Therefore, Piedmont believes that any unobservable inputs used to determine the estimated fair values of its derivative financial instruments are not significant to the fair value measurements in their entirety, and does not consider any of its derivative financial instruments to be Level 3 liabilities.

Impairment Loss on Real Estate

Impairment Loss on Real Estate Assets	9 Months Ended
	Sep. 30, 2016
Real Estate [Abstract]
Impairment Loss on Real Estate Assets	Impairment Loss on Real Estate Assets Piedmont recorded impairment loss on real estate assets for the three and nine months ended September 30, 2016 and 2015 , respectively, as follows (in thousands): Three Months Ended Nine Months Ended 2016 2015 2016 2015 Eastpoint I & II (1) $ — $ — $ — $ 5,354 2 Gatehall Drive (1) — 34,815 — 34,815 150 West Jefferson (1) — — 5,972 — 9221 Corporate Boulevard (2) — — 2,336 — 9200 and 9211 Corporate Boulevard (3) 22,590 — 22,590 — Total impairment loss on real estate assets (4) $ 22,590 $ 34,815 $ 30,898 $ 40,169 (1) Piedmont recognized an impairment loss on real estate assets based upon the difference between the carrying value of the asset and the contracted sales price, less estimated selling costs. (2) Piedmont, using a probability-weighted model heavily weighted towards the short-term sale of the 9221 Corporate Boulevard building in Rockville, Maryland, determined that the carrying value would not be recovered from the undiscounted future operating cash flows expected from the use of the asset and its eventual disposition. As a result, Piedmont recognized a loss on impairment of approximately $2.3 million during the nine months ended September 30, 2016 calculated as the difference between the carrying value of the asset and the anticipated contract sales price, less estimated selling costs. (3) Piedmont elected to sell its remaining two assets and exit the Rockville, Maryland sub-market of Washington, D.C, after selling the 9221 Corporate Boulevard building in July 2016 (mentioned above). Upon management's change in its hold period assumption for the assets from a long-term hold to a near-term sale, Piedmont recognized an impairment loss of approximately $22.6 million . The impairment loss was calculated as the difference between the carrying value of the asset and the anticipated contracted sales price, less estimated selling costs. Piedmont reclassified the properties as held for sale, recognized an impairment loss, entered into a binding contract, and subsequently sold the 9200 and 9211 Corporate Boulevard buildings during the three months ended September 30, 2016. (4) The fair value measurements used in the evaluation of the non-financial assets above are considered to be Level 1 valuations within the fair value hierarchy as defined by GAAP, as there are direct observations and transactions involving the assets by unrelated, third-party purchasers.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2016
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Commitments Under Existing Lease Agreements Under its existing lease agreements, Piedmont may be required to fund significant tenant improvements, leasing commissions, and building improvements. In addition, certain agreements contain provisions that require Piedmont to issue corporate or property guarantees to provide funding for capital improvements or other financial obligations. Piedmont classifies its capital improvements into two categories: (i) improvements which maintain the building's existing asset value and its revenue generating capacity (“non-incremental capital expenditures”) and (ii) improvements which incrementally enhance the building's asset value by expanding its revenue generating capacity (“incremental capital expenditures”). As of September 30, 2016 , commitments to fund potential non-incremental capital expenditures over the next five years for tenant improvements totaled approximately $37.7 million related to Piedmont's existing lease portfolio over the respective lease terms, the majority of which Piedmont estimates may be required to be funded over the next three years based on when the underlying leases commence. For most of Piedmont’s leases, the timing of the actual funding of these tenant improvements is largely dependent upon tenant requests for reimbursement. In some cases, these obligations may expire with the leases without further recourse to Piedmont. As of September 30, 2016 , commitments for incremental capital expenditures for tenant improvements associated with executed leases totaled approximately $31.3 million . Contingencies Related to Tenant Audits/Disputes Certain lease agreements include provisions that grant tenants the right to engage independent auditors to audit their annual operating expense reconciliations. Such audits may result in the re-interpretation of language in the lease agreements which could result in the refund of previously recognized tenant reimbursement revenues, resulting in financial loss to Piedmont. Piedmont recorded no such reductions in reimbursement revenues related to such tenant audits/disputes during the three and nine months ended September 30, 2016 , and $0 and $0.1 million for the three and nine months ended September 30, 2015 , respectively. Additionally, from time to time, tenants may attempt to dispute language in their lease agreements which could result in the refund of previously recognized tenant revenues, resulting in financial loss to Piedmont. During the three months ended September 30, 2016 , Piedmont filed suit against one such tenant. While Piedmont believes it will ultimately prevail in this matter, due to the uncertainties inherent in any litigation, Piedmont has determined that the risk of financial loss is reasonably possible. As of September 30, 2016 , the range of reasonably possible loss, net of reserves, is estimated to be $0 to $1.8 million .

Property Dispositions, Assets H

Property Dispositions, Assets Held for Sale, and Discontinued Operations	9 Months Ended
	Sep. 30, 2016
Discontinued Operations and Disposal Groups [Abstract]
Property Dispositions, Assets Held for Sale, and Discontinued Operations	Property Dispositions, Assets Held for Sale, and Discontinued Operations Properties sold during the nine months ended September 30, 2016 and 2015 did not meet the criteria to be reported as discontinued operations. The operational results for these properties prior to their sale dates are presented as continuing operations in the accompanying consolidated statements of income, and the gain/(loss) on sale is presented separately on the face of the income statement. Details of such properties sold are presented below (in thousands): Buildings Sold (1) Location Date of Sale Gain/(Loss) on Sale Net Sales Proceeds 3900 Dallas Parkway Plano, Texas January 30, 2015 $ 10,073 $ 25,803 5601 Headquarters Drive Plano, Texas April 28, 2015 $ 7,959 $ 33,326 River Corporate Center Tempe, Arizona April 29, 2015 $ 5,297 $ 24,223 Copper Ridge Center Lyndhurst, New Jersey May 1, 2015 $ 13,711 $ 50,372 (2) Eastpoint I & II Mayfield Heights, Ohio July 28, 2015 $ (177 ) $ 17,342 3750 Brookside Parkway Alpharetta, Georgia August 10, 2015 $ 1,406 $ 13,624 Chandler Forum Chandler, Arizona September 1, 2015 $ 15,506 $ 32,267 1055 East Colorado Pasadena, California April 21, 2016 $ 31,501 $ 60,076 Fairway Center II Brea, California April 28, 2016 $ 15,468 $ 33,063 1901 Main Street Irvine, California May 2, 2016 $ 32,016 $ 63,149 (3) 9221 Corporate Boulevard Rockville, Maryland July 27, 2016 $ (191 ) $ 12,037 150 West Jefferson Detroit, Michigan July 29, 2016 $ 134 $ 78,642 9200 and 9211 Corporate Boulevard Rockville, Maryland September 28, 2016 $ — (4) $ 12,535 (1) The dispositions of Aon Center in Chicago, Illinois on October 29, 2015, and 2 Gatehall Drive in Parsippany, New Jersey on December 21, 2015 has impacted the comparative analysis of operating results for the three and nine months ended September 30, 2016. (2) As part of the transaction, Piedmont accepted a secured promissory note from the buyer for $45.4 million . During the nine months ended September 30, 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 part of the transaction, Piedmont accepted a secured promissory note from the buyer for $33.0 million ; however, the note receivable was repaid in full by September 30, 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. (4) As discussed in Note 8 above, Piedmont recognized an impairment loss of approximately $22.6 million during the three months ended September 30, 2016. As the sale was consummated within the same quarter, there was no gain or loss recognized upon the sale. Assets Held for Sale As of September 30, 2016, no assets met the criteria to be classified as held for sale; however, as the 150 West Jefferson building met the held-for-sale criteria as of June 30, 2016, it is presented as held for sale as of December 31, 2015 for comparative purposes. Details of amounts held for sale as of December 31, 2015 are presented below (in thousands): September 30, 2016 December 31, 2015 Real estate assets held for sale, net: Land $ — $ 9,759 Building and improvements, less accumulated depreciation of $0 and $32,162 as of September 30, 2016 and December 31, 2015, respectively — 66,840 Construction in progress — 15 Total real estate assets held for sale, net $ — $ 76,614 Other assets held for sale, net: Straight-line rent receivables $ — $ 4,729 Prepaid expenses and other assets — 66 Deferred lease costs, less accumulated amortization of $0 and $1,162 as of September 30, 2016 and December 31, 2015, respectively — 3,695 Total other assets held for sale, net $ — $ 8,490 Details comprising loss from discontinued operations activity on 1441 West Long Lake Road in Troy, Michigan, 11109 Sunset Hills Road in Reston, Virginia, and 1200 Enclave Parkway in Houston, Texas for the three and nine months ended ended September 30, 2016 and 2015 are presented below (in thousands): Three Months Ended Nine Months Ended September 30, 2016 September 30, 2015 September 30, 2016 September 30, 2015 Revenues: Rental income $ — $ 19 $ — $ 19 Tenant reimbursements — — — (3 ) — 19 — 16 Expenses: Property operating costs — 3 — 2 General and administrative (1 ) — — 1 (1 ) 3 — 3 Operating income 1 16 — 13 Loss on sale of real estate assets — (2 ) — (2 ) Income from discontinued operations $ 1 $ 14 $ — $ 11

Stock Based Compensation

Stock Based Compensation	9 Months Ended
	Sep. 30, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock Based Compensation	Stock Based Compensation From time to time, Piedmont has granted equity awards to all of its employees and independent directors. The deferred stock awards are determined by the Compensation Committee of the board of directors of Piedmont and typically vest on the award anniversary date ratably over a multi-year period. Piedmont also has a multi-year performance share program for certain of its employees whereby equity awards may be earned based on the relative performance of Piedmont's total stockholder return ("TSR") as compared with a predetermined peer group's total stockholder return over the same multi-year period. Shares, if earned, are not awarded until after the end of the multi-year performance period and vest upon award. Shares granted to independent directors generally vest over a one -year service period. A rollforward of Piedmont's equity based award activity for the nine months ended September 30, 2016 is as follows: Shares Weighted-Average Grant Date Fair Value Unvested Stock Awards as of December 31, 2015 959,446 $ 18.67 Deferred Stock Awards Granted 319,083 $ 19.96 Increase in Estimated Potential Future Performance Share Awards, net of forfeitures 115,655 $ 22.94 Performance Stock Awards Vested (53,287 ) $ 18.91 Deferred Stock Awards Vested (256,511 ) $ 18.58 Deferred Stock Awards Forfeited (17,922 ) $ 18.22 Unvested Stock Awards as of September 30, 2016 1,066,464 $ 19.67 The following table provides additional information regarding stock award activity during the three and nine months ended September 30, 2016 and 2015 , respectively (in thousands except for per share data): Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, Weighted-Average Grant Date Fair Value of Deferred Stock Granted During the Period (per share) $ — $ 18.31 $ 19.96 $ 17.59 Total Grant Date Fair Value of Deferred Stock Vested During the Period $ 108 $ 32 $ 4,766 $ 4,109 Share-based Liability Awards Paid During the Period (1) $ — $ — $ 1,127 $ — (1) Amount reflects the issuance of performance share awards related to the 2013-15 Performance Share Plan during the period. A detail of Piedmont’s outstanding stock awards as of September 30, 2016 is as follows: Date of grant Type of Award Net Shares Granted (1) Grant Date Fair Value Vesting Schedule Unvested Shares as of September 30, 2016 January 3, 2014 Deferred Stock Award 86,512 $ 16.45 Of the shares granted, 20% vested or will vest on January 3, 2015, 2016, 2017, 2018, and 2019, respectively. 52,886 May 9, 2014 Deferred Stock Award 145,330 $ 18.46 Of the shares granted, 25% vested on the date of grant, and 25% vested or will vest on May 9, 2015, 2016, and 2017, respectively. 46,555 May 9, 2014 Fiscal Year 2014-2016 Performance Share Program — $ 22.00 Shares awarded, if any, will vest immediately upon determination of award in 2017. 155,919 (2) May 1, 2015 Deferred Stock Award 243,884 $ 17.59 Of the shares granted, 25% vested on the date of grant, and 25% vested or will vest on May 1, 2016, 2017, and 2018, respectively. 138,816 May 1, 2015 Fiscal Year 2015-2017 Performance Share Program — $ 18.42 Shares awarded, if any, will vest immediately upon determination of award in 2018. 297,424 (2) May 12, 2016 Deferred Stock Award-Board of Directors 31,368 $ 20.40 Of the shares granted, 100% will vest on May 12, 2017. 31,368 May 24, 2016 Deferred Stock Award 259,957 $ 19.91 Of the shares granted, 25% vested on the date of grant, and 25% vested or will vest on May 24, 2017, 2018, and 2019, respectively. 207,412 May 24, 2016 Fiscal Year 2016-2018 Performance Share Program — $ 23.02 Shares awarded, if any, will vest immediately upon determination of award in 2019. 136,084 (2) Total 1,066,464 (1) Amounts reflect the total grant to employees and independent directors, net of shares surrendered upon vesting to satisfy required minimum tax withholding obligations through September 30, 2016 . (2) Estimated based on Piedmont's cumulative TSR for the respective performance period through September 30, 2016 . Share estimates are subject to change in future periods based on both Piedmont's and its peers' stock performance and dividends paid. During the three months ended September 30, 2016 and 2015 , Piedmont recognized approximately $2.0 million and $2.6 million of compensation expense related to stock awards, all of which related to the amortization of unvested shares. During the nine months ended September 30, 2016 and 2015 , Piedmont recognized approximately $7.7 million and $6.8 million of compensation expense related to stock awards, of which $6.2 million and $5.0 million related to the amortization of unvested shares, respectively. During the nine months ended September 30, 2016 , a net total of 183,609 shares were issued to employees. As of September 30, 2016 , approximately $5.0 million of unrecognized compensation cost related to unvested deferred stock awards remained, which Piedmont will record in its consolidated statements of income over a weighted-average vesting period of approximately one year.

Earnings Per Share

Earnings Per Share	9 Months Ended
	Sep. 30, 2016
Earnings Per Share [Abstract]
Earnings Per Share	Earnings Per Share There are no adjustments to “Net income applicable to Piedmont” for the diluted earnings per share computations. Net income per share-basic is calculated as net income available to common stockholders divided by the weighted average number of common shares outstanding during the period. Net income per share-diluted is calculated as net income available to common stockholders divided by the diluted weighted average number of common shares outstanding during the period, including unvested deferred stock awards. Diluted weighted average number of common shares reflects the potential dilution under the treasury stock method that would occur if the remaining unvested deferred stock awards vested and resulted in additional common shares outstanding. Unvested deferred stock awards which are determined to be anti-dilutive are not included in the calculation of diluted weighted average common shares. The following table reconciles the denominator for the basic and diluted earnings per share computations shown on the consolidated statements of income for the three and nine months ended September 30, 2016 and 2015 , respectively (in thousands): Three Months Ended Nine Months Ended September 30, 2016 September 30, 2015 September 30, 2016 September 30, 2015 Weighted-average common shares – basic 145,231 148,855 145,229 152,231 Plus incremental weighted-average shares from time-vested conversions: Deferred and performance stock awards 438 321 372 268 Weighted-average common shares – diluted (1) 145,669 149,176 145,601 152,499 (1) Due to repurchases of common stock during the current year, Piedmont has 145,233,753 shares of common stock outstanding as of September 30, 2016 .

Guarantor and Non-Guarantor Fin

Guarantor and Non-Guarantor Financial Information	9 Months Ended
	Sep. 30, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Guarantor and Non-Guarantor Financial Information	Guarantor and Non-Guarantor Financial Information The following condensed consolidating financial information for Piedmont Operating Partnership, L.P. (the "Issuer"), Piedmont Office Realty Trust, Inc. (the "Guarantor"), and the other directly and indirectly owned subsidiaries of the Guarantor (the "Non-Guarantor Subsidiaries") is provided pursuant to the requirements of Rule 3-10 of Regulation S-X regarding financial statements of guarantors and issuers of guaranteed registered securities. The Issuer is a wholly-owned subsidiary of the Guarantor, and all guarantees by the Guarantor of securities issued by the Issuer are full and unconditional. The principal elimination entries relate to investments in subsidiaries and intercompany balances and transactions, including transactions with the Non-Guarantor Subsidiaries. Condensed Consolidated Balance Sheets As of September 30, 2016 (in thousands) Issuer Guarantor Non-Guarantor Subsidiaries Eliminations Consolidated Assets: Real estate assets, at cost: Land $ 48,213 $ — $ 615,484 $ — $ 663,697 Buildings and improvements, less accumulated depreciation 238,912 — 2,659,027 (300 ) 2,897,639 Intangible lease assets, less accumulated amortization 861 — 91,495 — 92,356 Construction in progress 1,136 — 33,950 — 35,086 Total real estate assets 289,122 — 3,399,956 (300 ) 3,688,778 Investments in and amounts due from unconsolidated joint ventures 7,351 — — — 7,351 Cash and cash equivalents 3,591 150 2,291 — 6,032 Tenant and straight-line rent receivables, net 20,398 — 163,198 — 183,596 Advances to affiliates 6,350,066 1,284,119 — (7,634,185 ) — Investment in subsidiary — 3,661,064 182 (3,661,246 ) — Notes receivable 88,910 — 95,790 (184,700 ) — Prepaid expenses, restricted cash, escrows, and other assets 12,148 37 23,444 (1,703 ) 33,926 Goodwill 180,097 — — — 180,097 Deferred lease costs, net 17,486 — 271,031 — 288,517 Total assets $ 6,969,169 $ 4,945,370 $ 3,955,892 $ (11,482,134 ) $ 4,388,297 Liabilities: Debt, net $ 1,675,263 $ — $ 503,515 $ (184,700 ) $ 1,994,078 Accounts payable, accrued expenses, and accrued capital expenditures 18,061 644 116,111 (1,704 ) 133,112 Advances from affiliates 659,326 5,071,498 1,998,428 (7,729,252 ) — Deferred income 6,741 — 22,265 — 29,006 Intangible lease liabilities, net — — 45,283 — 45,283 Interest rate swaps 17,835 — — — 17,835 Total liabilities 2,377,226 5,072,142 2,685,602 (7,915,656 ) 2,219,314 Stockholders’ Equity: Common stock — 1,452 — — 1,452 Additional paid-in capital 3,657,063 3,675,090 1,310 (3,661,245 ) 3,672,218 Retained/(cumulative distributions in excess of) earnings 942,091 (3,803,314 ) 1,267,082 94,767 (1,499,374 ) Other comprehensive loss (7,211 ) — — — (7,211 ) Piedmont stockholders’ equity 4,591,943 (126,772 ) 1,268,392 (3,566,478 ) 2,167,085 Noncontrolling interest — — 1,898 — 1,898 Total stockholders’ equity 4,591,943 (126,772 ) 1,270,290 (3,566,478 ) 2,168,983 Total liabilities and stockholders’ equity $ 6,969,169 $ 4,945,370 $ 3,955,892 $ (11,482,134 ) $ 4,388,297 Condensed Consolidated Balance Sheets As of December 31, 2015 (in thousands) Issuer Guarantor Non-Guarantor Subsidiaries Eliminations Consolidated Assets: Real estate assets, at cost: Land $ 54,459 $ — $ 621,632 $ — $ 676,091 Buildings and improvements, less accumulated depreciation 270,057 — 2,567,706 (300 ) 2,837,463 Intangible lease assets, less accumulated amortization 1,268 — 83,395 — 84,663 Construction in progress 240 — 20,735 — 20,975 Real estate assets held for sale, net 76,614 — — — 76,614 Total real estate assets 402,638 — 3,293,468 (300 ) 3,695,806 Investments in and amounts due from unconsolidated joint ventures 7,577 — — — 7,577 Cash and cash equivalents 2,174 150 3,117 — 5,441 Tenant and straight-line rent receivables, net 23,738 — 149,994 — 173,732 Advances to affiliates 6,073,606 1,251,530 — (7,325,136 ) — Investment in subsidiary — 3,752,523 186 (3,752,709 ) — Notes receivable 134,750 — 23,890 (113,240 ) 45,400 Prepaid expenses, restricted cash, escrows, and other assets 7,091 — 24,118 (1,258 ) 29,951 Goodwill 180,097 — — — 180,097 Deferred lease costs, net 20,939 — 267,102 — 288,041 Other assets held for sale, net 8,490 — — — 8,490 Total assets $ 6,861,100 $ 5,004,203 $ 3,761,875 $ (11,192,643 ) $ 4,434,535 Liabilities: Debt, net $ 1,552,007 $ — $ 590,743 $ (113,240 ) $ 2,029,510 Accounts payable, accrued expenses, and accrued capital expenditures 18,954 580 110,189 (1,258 ) 128,465 Advances from affiliates 580,526 5,033,266 1,788,840 (7,402,632 ) — Deferred income 5,905 — 21,365 — 27,270 Intangible lease liabilities, net — — 42,853 — 42,853 Interest rate swaps 9,993 — — — 9,993 Total liabilities 2,167,385 5,033,846 2,553,990 (7,517,130 ) 2,238,091 Stockholders’ Equity: Common stock — 1,455 — — 1,455 Additional paid-in capital 3,748,524 3,672,849 1,314 (3,752,710 ) 3,669,977 Retained/(cumulative distributions in excess of) earnings 943,530 (3,703,947 ) 1,205,546 77,197 (1,477,674 ) Other comprehensive income 1,661 — — — 1,661 Piedmont stockholders’ equity 4,693,715 (29,643 ) 1,206,860 (3,675,513 ) 2,195,419 Noncontrolling interest — — 1,025 — 1,025 Total stockholders’ equity 4,693,715 (29,643 ) 1,207,885 (3,675,513 ) 2,196,444 Total liabilities and stockholders’ equity $ 6,861,100 $ 5,004,203 $ 3,761,875 $ (11,192,643 ) $ 4,434,535 Condensed Consolidated Statements of Income For the three months ended September 30, 2016 (in thousands) Issuer Guarantor Non-Guarantor Subsidiaries Eliminations Consolidated Revenues: Rental income $ 12,862 $ — $ 101,423 $ (464 ) $ 113,821 Tenant reimbursements 3,430 — 20,970 (237 ) 24,163 Property management fee revenue — — 3,985 (3,484 ) 501 16,292 — 126,378 (4,185 ) 138,485 Expenses: Property operating costs 7,820 — 51,287 (4,240 ) 54,867 Depreciation 3,617 — 27,993 — 31,610 Amortization 863 — 17,777 — 18,640 Impairment loss on real estate assets — — 22,590 — 22,590 General and administrative 7,187 83 9,016 (8,857 ) 7,429 19,487 83 128,663 (13,097 ) 135,136 Real estate operating income/(loss) (3,195 ) (83 ) (2,285 ) 8,912 3,349 Other income (expense): Interest expense (11,799 ) — (6,949 ) 3,252 (15,496 ) Other income/(expense) 2,608 — (76 ) (3,252 ) (720 ) Recovery from casualty event — — 34 — 34 Equity in income of unconsolidated joint ventures 128 — — — 128 (9,063 ) — (6,991 ) — (16,054 ) Income/(loss) from continuing operations (12,258 ) (83 ) (9,276 ) 8,912 (12,705 ) Discontinued operations: Operating income — — 1 — 1 Income from discontinued operations — — 1 — 1 Gain/(loss) on sale of real estate assets 134 — (191 ) — (57 ) Net income/(loss) (12,124 ) (83 ) (9,466 ) 8,912 (12,761 ) Less: Net loss applicable to noncontrolling interest — — 15 — 15 Net income/(loss) applicable to Piedmont $ (12,124 ) $ (83 ) $ (9,451 ) $ 8,912 $ (12,746 ) Condensed Consolidated Statements of Income For the three months ended September 30, 2015 (in thousands) Issuer Guarantor Non-Guarantor Subsidiaries Eliminations Consolidated Revenues: Rental income $ 15,841 $ — $ 102,888 $ (735 ) $ 117,994 Tenant reimbursements 3,369 — 26,935 (31 ) 30,273 Property management fee revenue — — 4,603 (4,055 ) 548 19,210 — 134,426 (4,821 ) 148,815 Expenses: Property operating costs 9,238 — 57,446 (5,031 ) 61,653 Depreciation 4,943 — 26,256 — 31,199 Amortization 1,126 — 12,895 — 14,021 Impairment loss on real estate assets — — 34,815 — 34,815 General and administrative 8,118 71 9,506 (9,435 ) 8,260 23,425 71 140,918 (14,466 ) 149,948 Real estate operating income/(loss) (4,215 ) (71 ) (6,492 ) 9,645 (1,133 ) Other income (expense): Interest expense (12,963 ) — (8,413 ) 2,544 (18,832 ) Other income/(expense) 3,199 — 148 (2,544 ) 803 Equity in income of unconsolidated joint ventures 135 — — — 135 (9,629 ) — (8,265 ) — (17,894 ) Income/(loss) from continuing operations (13,844 ) (71 ) (14,757 ) 9,645 (19,027 ) Discontinued operations: Operating income 16 — — — 16 Loss on sale of real estate assets (2 ) — — — (2 ) Income from discontinued operations 14 — — — 14 Gain on sale of real estate assets 17,142 — — — 17,142 Net income/(loss) 3,312 (71 ) (14,757 ) 9,645 (1,871 ) Less: Net income applicable to noncontrolling interest — — (4 ) — (4 ) Net income/(loss) applicable to Piedmont $ 3,312 $ (71 ) $ (14,761 ) $ 9,645 $ (1,875 ) Condensed Consolidated Statements of Income For the nine months ended September 30, 2016 (in thousands) Issuer Guarantor Non-Guarantor Subsidiaries Eliminations Consolidated Revenues: Rental income $ 42,990 $ — $ 299,319 $ (1,983 ) $ 340,326 Tenant reimbursements 10,455 — 59,950 (405 ) 70,000 Property management fee revenue — — 12,480 (11,002 ) 1,478 53,445 — 371,749 (13,390 ) 411,804 Expenses: Property operating costs 24,583 — 150,369 (13,514 ) 161,438 Depreciation 12,993 — 81,955 — 94,948 Amortization 2,854 — 50,994 — 53,848 Impairment loss on real estate assets 5,972 — 24,926 — 30,898 General and administrative 22,802 251 28,881 (28,416 ) 23,518 69,204 251 337,125 (41,930 ) 364,650 Real estate operating income/(loss) (15,759 ) (251 ) 34,624 28,540 47,154 Other income (expense): Interest expense (36,159 ) — (20,354 ) 8,219 (48,294 ) Other income/(expense) 7,008 282 462 (8,219 ) (467 ) Recovery from casualty event — — 34 — 34 Equity in income of unconsolidated joint ventures 354 — — — 354 (28,797 ) 282 (19,858 ) — (48,373 ) Income/(loss) from continuing operations (44,556 ) 31 14,766 28,540 (1,219 ) Gain on sale of real estate assets, net 32,146 — 46,764 — 78,910 Net income/(loss) (12,410 ) 31 61,530 28,540 77,691 Less: Net loss applicable to noncontrolling interest — — 7 — 7 Net income/(loss) applicable to Piedmont $ (12,410 ) $ 31 $ 61,537 $ 28,540 $ 77,698 Condensed Consolidated Statements of Income For the nine months ended September 30, 2015 (in thousands) Issuer Guarantor Non-Guarantor Subsidiaries Eliminations Consolidated Revenues: Rental income $ 51,824 $ — $ 303,603 $ (2,172 ) $ 353,255 Tenant reimbursements 11,171 — 79,634 (329 ) 90,476 Property management fee revenue — — 13,543 (11,966 ) 1,577 62,995 — 396,780 (14,467 ) 445,308 Expenses: Property operating costs 29,459 — 172,977 (15,068 ) 187,368 Depreciation 15,904 — 87,566 — 103,470 Amortization 3,477 — 40,169 — 43,646 Impairment loss of real estate assets 5,354 — 34,815 — 40,169 General and administrative 22,211 266 26,504 (26,231 ) 22,750 76,405 266 362,031 (41,299 ) 397,403 Real estate operating income/(loss) (13,410 ) (266 ) 34,749 26,832 47,905 Other income (expense): Interest expense (39,592 ) — (25,130 ) 8,702 (56,020 ) Other income/(expense) 9,357 — 563 (8,702 ) 1,218 Equity in income of unconsolidated joint ventures 418 — — — 418 (29,817 ) — (24,567 ) — (54,384 ) Income/(loss) from continuing operations (43,227 ) (266 ) 10,182 26,832 (6,479 ) Discontinued operations: Operating income 13 — — — 13 Loss on sale of real estate assets (2 ) — — — (2 ) Income from discontinued operations 11 — — — 11 Gain on sale of real estate assets, net 53,826 — — — 53,826 Net income/(loss) 10,610 (266 ) 10,182 26,832 47,358 Less: Net income applicable to noncontrolling interest — — (12 ) — (12 ) Net income/(loss) applicable to Piedmont $ 10,610 $ (266 ) $ 10,170 $ 26,832 $ 47,346 Condensed Consolidated Statements of Cash Flows For the nine months ended September 30, 2016 (in thousands) Issuer Guarantor Non-Guarantor Subsidiaries Eliminations Consolidated Net Cash Provided by Operating Activities $ (18,977 ) $ 4,121 $ 158,352 $ 28,540 $ 172,036 Cash Flows from Investing Activities: Investment in real estate assets, consolidated joint venture, and real estate related intangibles, net of accruals (24,255 ) — (296,884 ) — (321,139 ) Intercompany note receivable 440 — (71,900 ) 71,460 — Net sales proceeds from wholly-owned properties 187,192 — 117,710 — 304,902 Deferred lease costs paid (2,021 ) — (13,324 ) — (15,345 ) Net cash provided by/(used in) investing activities 161,356 — (264,398 ) 71,460 (31,582 ) Cash Flows from Financing Activities: Debt issuance costs paid (212 ) — — — (212 ) Proceeds from debt 552,000 — — — 552,000 Repayments of debt (421,000 ) — (168,532 ) — (589,532 ) Intercompany note payable (9,600 ) — 81,060 (71,460 ) — Costs of issuance of common stock — (239 ) — — (239 ) Shares withheld to pay tax obligations related to employee stock compensation — (2,328 ) — — (2,328 ) Repurchases of common stock as part of announced plan — (7,943 ) — — (7,943 ) (Distributions to)/repayments from affiliates (262,150 ) 97,990 192,700 (28,540 ) — Dividends paid and discount on dividend reinvestments — (91,601 ) (8 ) — (91,609 ) Net cash provided by/(used in) financing activities (140,962 ) (4,121 ) 105,220 (100,000 ) (139,863 ) Net increase/(decrease) in cash and cash equivalents 1,417 — (826 ) — 591 Cash and cash equivalents, beginning of period 2,174 150 3,117 — 5,441 Cash and cash equivalents, end of period $ 3,591 $ 150 $ 2,291 $ — $ 6,032 Condensed Consolidated Statements of Cash Flows For the nine months ended September 30, 2015 (in thousands) Issuer Guarantor Non-Guarantor Subsidiaries Eliminations Consolidated Net Cash Provided by Operating Activities $ (41,584 ) $ 3,772 $ 145,240 $ 26,833 $ 134,261 Cash Flows from Investing Activities: Investment in real estate assets and real estate related intangibles, net of accruals (28,249 ) — (129,644 ) — (157,893 ) Intercompany note receivable 72,000 — — (72,000 ) — Redemption of noncontrolling interest in unconsolidated variable interest entity — — (4,000 ) — (4,000 ) Net sales proceeds from wholly-owned properties 151,564 — — — 151,564 Deferred lease costs paid (2,577 ) — (21,312 ) — (23,889 ) Net cash provided by/(used in) investing activities 192,738 — (154,956 ) (72,000 ) (34,218 ) Cash Flows from Financing Activities: Debt issuance costs paid (545 ) — (503 ) — (1,048 ) Proceeds from debt 1,046,578 — 159,279 — 1,205,857 Repayments of debt (950,000 ) — (177,902 ) 72,000 (1,055,902 ) Costs of issuance of common stock — (326 ) — — (326 ) Shares withheld to pay tax obligations related to employee stock compensation — (1,665 ) — — (1,665 ) Repurchases of common stock as part of announced plan — (155,653 ) — — (155,653 ) (Distributions to)/repayments from affiliates (251,395 ) 248,135 30,093 (26,833 ) — Dividends paid and discount on dividend reinvestments — (95,902 ) (8 ) — (95,910 ) Net cash provided/(used in) by financing activities (155,362 ) (5,411 ) 10,959 45,167 (104,647 ) Net increase/(decrease) in cash and cash equivalents (4,208 ) (1,639 ) 1,243 — (4,604 ) Cash and cash equivalents, beginning of period 8,143 1,790 2,373 — 12,306 Cash and cash equivalents, end of period $ 3,935 $ 151 $ 3,616 $ — $ 7,702

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2016
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events Fourth Quarter Dividend Declaration On November 1, 2016 , the board of directors of Piedmont declared dividends for the fourth quarter 2016 in the amount of $0.21 per common share outstanding to stockholders of record as of the close of business on November 25, 2016 . Such dividends are to be paid on January 3, 2017 . Acquisitions On October 7, 2016, Piedmont acquired the Galleria 200 building located in Atlanta, Georgia for $69.6 million .

Summary of Significant Accoun23

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2016
Accounting Policies [Abstract]
Basis of Presentation	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.
Principles of Consolidation	Piedmont’s consolidated financial statements include the accounts of Piedmont, Piedmont’s wholly-owned subsidiaries, any variable interest entity ("VIE") of which Piedmont or any of its wholly-owned subsidiaries is considered to have the power to direct the activities of the entity and the obligation to absorb losses/right to receive benefits, or any entity in which Piedmont or any of its wholly-owned subsidiaries owns a controlling interest. In determining whether Piedmont or Piedmont OP has a controlling interest, the following factors, among others, are considered: equity ownership, voting rights, protective rights of investors, and participatory rights of investors. 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, 2015 . 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. Consequently, the assets of these 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	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.
Income Taxes	Income Taxes Piedmont has elected to be taxed as a REIT under the Internal Revenue Code of 1986, as amended, 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, subject to fulfilling, among other things, this distribution requirement. 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.
Tenant Receivables, net and Straight-line Rent Receivables	Tenant Receivables, net and Straight-line Rent Receivables Tenant receivables are comprised of rental and reimbursement billings due from tenants, and straight-line rent receivables representing the cumulative amount of future adjustments necessary to present rental income on a straight-line basis. Tenant receivables are recorded at the original amount earned, less an allowance for any doubtful accounts, which approximates estimated fair value. Management assesses the collectibility of tenant receivables on an ongoing basis and provides for allowances as such balances, or portions thereof, become uncollectible. Effective July 1, 2016, Piedmont began classifying provisions for bad debts as nonrecoverable property operating costs in the accompanying consolidated statements of income to include such expenses as a component of operating the underlying properties. Previously, such costs were presented as general and administrative expenses.
Accounting Pronouncements Adopted and Other Recent Accounting Pronouncements	Accounting Pronouncements Adopted during the Nine Months Ended September 30, 2016 As of January 1, 2016, Piedmont early adopted the provisions of Financial Accounting Standards Board (the "FASB") Accounting Standards Update No. 2016-09, Compensation- Stock Compensation (Topic 718) Improvements to Employee Share-Based Payment Accounting ("ASU 2016-09"). The provisions in ASU 2016-09 simplify the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities, and classification on the statement of cash flows. The implementation of ASU 2016-09 resulted in the reclassification of approximately $1.7 million related to income tax consequences for share-based compensation from cash outflows from operating activities to cash outflows from financing activities in the accompanying consolidated statements of cash flows for the nine months ended September 30, 2015. Additionally, as of January 1, 2016, Piedmont also adopted Accounting Standards Update No. 2015-05, Intangibles- Goodwill and Other- Internal-Use Software (Subtopic 350-40) “Customer’s Accounting for Fees Paid in a Cloud Computing Arrangement on a prospective basis. Other Recent Accounting Pronouncements The FASB has issued Accounting Standards Update No. 2016-05, Derivatives and Hedging (Topic 815), Effect of Derivative Contract Novations on Existing Hedge Accounting Relationships ("ASU 2016-05"). The amendments in ASU 2016-05 clarify that a change in the counterparty to a derivative instrument that has been designated as the hedging instrument does not, in and of itself, require de-designation of that hedging relationship provided that all other hedge accounting criteria continue to be met. The amendments in ASU 2016-05 are effective in the first quarter of 2017, and Piedmont does not anticipate any material impact to its consolidated financial statements as a result of adoption. The FASB has issued Accounting Standards Update No. 2014-09, Revenue from Contracts with Customers (Topic 606) ("ASU 2014-09") and Accounting Standards Update No. 2016-08, Revenue from Contracts with Customers (Topic 606) Principal versus Agent Considerations (Reporting Revenue Gross versus Net) ("ASU 2016-08"). The amendments in ASU 2014-09, which are further clarified in ASU 2016-08, as well as ASU 2016-10 and ASU 2016-12, change the criteria for the recognition of revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services using a five-step determination process. Steps 1 through 5 involve (i) identifying contracts with a customer, (ii) identifying the performance obligations in the contract, (iii) determining the transaction price, (iv) allocating the transaction price to the performance obligations, and (v) recognizing revenue as an entity satisfies a performance obligation. Additionally, lease contracts are specifically excluded from ASU 2014-09. The amendments in ASU 2014-09 and ASU 2016-08 are effective in the first quarter of 2018, and Piedmont is currently evaluating the potential impact, if any, of adoption. The FASB has issued Accounting Standards Update No. 2016-01, Financial Instruments - Overall (Subtopic 825-10), Recognition and Measurement of Financial Assets and Financial Liabilities ("ASU 2016-01"). The amendments in ASU 2016-01 require equity investments, except those accounted for under the equity method of accounting, to be measured at estimated fair value with changes in fair value recognized in net income. Additionally, ASU 2016-01 simplifies the impairment assessment of equity investments, and eliminates certain disclosure requirements. The amendments in ASU 2016-01 are effective in the first quarter of 2018, and Piedmont is currently evaluating the potential impact of adoption. The FASB has issued Accounting Standards Update No. 2016-02, Leases (Topic 842), ("ASU 2016-02"). The amendments in ASU 2016-02 fundamentally change the definition of a lease, as well as the accounting for operating leases by requiring leasees to recognize assets and liabilities which arise from the lease, consisting of a liability to make lease payments (the lease liability) and a right-of-use asset, representing the right to use the leased asset over the term of the lease. Accounting for leases for lessors is substantially unchanged from prior practice, which means continuing to recognize lease revenue on a straight-line basis. The amendments in ASU 2016-02 are effective in the first quarter of 2019, and Piedmont is currently evaluating the potential impact of adoption. The FASB has issued Accounting Standards Update No. 2016-13, Financial Instruments—Credit Losses (Topic 326), Measurement of Credit Losses on Financial Instruments ("ASU 2016-13"). The provisions of ASU 2016-13 replace the "incurred loss" approach with an "expected loss" model for impairing trade and other receivables, held-to-maturity debt securities, net investment in leases, and off-balance-sheet credit exposures, which will generally result in earlier recognition of allowance for losses. Additionally, the provisions change the classification of credit losses on available-for-sale securities as an allowance rather than reductions in the amortized cost of the securities. ASU 2016-13 is effective in the first quarter of 2020, with early adoption permitted as of January 1, 2019. Piedmont is currently evaluating the potential impact of adoption. The FASB has issued Accounting Standards Update No. 2016-15, Statement of Cash Flows (Topic 230), Classification of Certain Cash Receipts and Cash Payments ("ASU 2016-15"). The provisions of ASU 2016-15 provide clarity of treatment in the statement of cash flows for several transactions, including debt repayments or debt extinguishment costs, proceeds received from the settlement of insurance claims, and distributions received from equity method investees, among several other topics. The FASB issued ASU 2016-15 in an effort to eliminate diversity in practice regarding treatment of specific transactions in the statements of cash flows for registrants. ASU 2016-15 is effective for Piedmont in the first quarter of 2018, with early adoption permitted. Piedmont is currently evaluating the potential impact of adoption.

Acquisitions (Tables)

Acquisitions (Tables)	9 Months Ended
	Sep. 30, 2016
Business Combinations [Abstract]
Schedule of Business Acquisitions, by Acquisition	During the nine months ended September 30, 2016 , Piedmont acquired one property, as well as a 99% interest in a joint venture owning two properties, using proceeds from the $500 Million Unsecured 2015 Line of Credit, proceeds from the sales of other properties, and cash on hand, as noted below: Property Metropolitan Statistical Area Date of Acquisition Ownership Percentage Acquired Rentable Square Feet (Unaudited) Percentage Leased as of Acquisition (Unaudited) Net Contractual Purchase Price (in millions) CNL Tower I & II Orlando, Florida August 1, 2016 99 % 622,488 95 % $ 166.7 One Wayside Road Boston, Massachusetts August 10, 2016 100 % 200,605 100 % $ 62.9

Debt (Tables)

Debt (Tables)	9 Months Ended
	Sep. 30, 2016
Debt Disclosure [Abstract]
Schedule of Debt	The following table summarizes the terms of Piedmont’s indebtedness outstanding as of September 30, 2016 and December 31, 2015 (in thousands): Facility (1) Stated Rate Effective Rate (2) Maturity Amount Outstanding as of 2016 2015 Secured (Fixed) $125 Million Fixed-Rate Loan 5.50 % 5.50 % 4/1/2016 $ — $ 125,000 $42.5 Million Fixed-Rate Loan 5.70 % 5.70 % 10/11/2016 — 42,525 $140 Million WDC Fixed-Rate Loans (3) 5.76 % 5.76 % 11/1/2017 140,000 140,000 $35 Million Fixed-Rate Loan (4) 5.55 % 3.75 % 9/1/2021 31,802 32,445 $160 Million Fixed-Rate Loan (5) 3.48 % 3.58 % 7/5/2022 160,000 160,000 Net premium and unamortized debt issuance costs 1,210 1,319 Subtotal/Weighted Average (6) 4.64 % 333,012 501,289 Unsecured (Variable and Fixed) $170 Million Unsecured 2015 Term Loan (7) LIBOR + 1.125% 1.66 % 5/15/2018 170,000 170,000 $300 Million Unsecured 2013 Term Loan LIBOR + 1.20% 2.78 % 1/31/2019 300,000 300,000 $500 Million Unsecured 2015 Line of Credit (7) LIBOR + 1.00% 1.53 % 6/18/2019 (8) 152,000 21,000 $300 Million Unsecured 2011 Term Loan (9) LIBOR + 1.15% 2.39 % 1/15/2020 300,000 300,000 $350 Million Senior Notes 3.40 % 3.43 % 6/01/2023 350,000 350,000 $400 Million Senior Notes 4.45 % 4.10 % 3/15/2024 400,000 400,000 Discounts and unamortized debt issuance costs (10,934) (12,779) Subtotal/Weighted Average (6) 3.01 % 1,661,066 1,528,221 Total/Weighted Average (6) 3.28 % $ 1,994,078 $ 2,029,510 (1) Other than the $35 Million Fixed-Rate Loan, all of Piedmont’s outstanding debt as of September 30, 2016 and December 31, 2015 is interest-only. (2) Effective rate after consideration of settled or in place interest rate swap agreements and/or issuance premiums or discounts. (3) Collateralized by the 1201 and 1225 Eye Street buildings in Washington, D.C. (4) Collateralized by the 5 Wall Street building in Burlington, Massachusetts. (5) Collateralized by the 1901 Market Street building in Philadelphia, Pennsylvania. (6) Weighted average is based on contractual balance of outstanding debt and the stated or effectively fixed interest rates in the table as of September 30, 2016 . (7) On a periodic basis, Piedmont may select from multiple interest rate options, including the prime rate and various-length LIBOR locks. All LIBOR selections are subject to an additional spread over the selected rate based on Piedmont’s current credit rating. (8) Piedmont may extend the term for up to one additional year (through two available six month extensions to a final extended maturity date of June 18, 2020) provided Piedmont is not then in default and upon payment of extension fees. (9) The $300 Million Unsecured 2011 Term Loan has a stated variable rate; however, Piedmont has entered into interest rate swap agreements which effectively fix, exclusive of changes to Piedmont's credit rating, the rate on this facility to 2.39% through the original maturity date of November 22, 2016 and 3.35% from November 22, 2016 to January 15, 2020.

Variable Interest Entities (Tab

Variable Interest Entities (Tables)	9 Months Ended
	Sep. 30, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Variable Interest Entities	A summary of Piedmont’s interests in, and consolidation treatment of, its VIEs and their related carrying values as of September 30, 2016 and December 31, 2015 is as follows (net carrying amount in millions): Entity Piedmont’s % Ownership of Entity Related Building Consolidated/ Unconsolidated Net Carrying Amount as of September 30, 2016 Net Carrying Amount as of December 31, 2015 Primary Beneficiary Considerations 1201 Eye Street N.W. Associates, LLC 49.5% 1201 Eye Street Consolidated $ (7.1 ) $ (7.4 ) In accordance with the partnership’s governing documents, Piedmont is entitled to 100% of the cash flow of the entity and has sole discretion in directing the management and leasing activities of the building. 1225 Eye Street N.W. Associates, LLC 49.5% 1225 Eye Street Consolidated $ 9.9 $ 3.8 In accordance with the partnership’s governing documents, Piedmont is entitled to 100% of the cash flow of the entity and has sole discretion in directing the management and leasing activities of the building. Piedmont 500 W. Monroe Fee, LLC 100% 500 W. Monroe Consolidated $ 263.1 $ 251.4 The Omnibus Agreement with the previous owner includes equity participation rights for the previous owner, if certain financial returns are achieved; however, Piedmont has sole decision making authority and is entitled to 100% of the economic benefits of the property until such returns are met.

Derivative Instruments (Tables)

Derivative Instruments (Tables)	9 Months Ended
	Sep. 30, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Notional Amounts of Outstanding Derivative Positions	A detail of Piedmont’s interest rate derivatives outstanding as of September 30, 2016 is as follows: Interest Rate Derivatives: Number of Swap Agreements Associated Debt Instrument Total Notional Amount (in millions) Effective Date Maturity Date Interest rate swaps 4 $300 Million Unsecured 2011 Term Loan $ 300 11/22/2011 11/22/2016 Interest rate swaps 4 $300 Million Unsecured 2013 Term Loan 200 1/30/2014 1/31/2019 Interest rate swaps 2 $300 Million Unsecured 2013 Term Loan 100 8/29/2014 1/31/2019 Forward starting interest rate swaps 3 $300 Million Unsecured 2011 Term Loan 300 11/22/2016 1/15/2020 Total $ 900
Schedule of Interest Rate Derivatives	A detail of Piedmont’s interest rate derivatives on a gross and net basis as of September 30, 2016 and December 31, 2015 , respectively, is as follows (in thousands): Interest rate swaps classified as: September 30, December 31, Gross derivative assets $ — $ — Gross derivative liabilities 17,835 9,993 Net derivative liability $ 17,835 $ 9,993
Schedule of Derivative Instruments, Effect on Other Comprehensive Income (Loss)	The effective portion of Piedmont's interest rate derivatives, including the gain/(loss) on previously settled forward swaps, that was recorded in the accompanying consolidated statements of income for the three and nine months ended September 30, 2016 and 2015 , respectively, was as follows (in thousands): Three Months Ended Nine Months Ended Interest Rate Swaps in Cash Flow Hedging Relationships September 30, September 30, September 30, September 30, Amount of gain/(loss) recognized in OCI on derivative $ 2,847 $ (22,263 ) $ (12,182 ) $ (21,389 ) Amount of previously recorded loss reclassified from accumulated OCI into interest expense $ 1,045 $ 1,506 $ 3,291 $ 4,575

Fair Value Measurement of Fin28

Fair Value Measurement of Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2016
Fair Value Disclosures [Abstract]
Fair Value, by Balance Sheet Grouping	The following table sets forth the carrying and estimated fair value for each of Piedmont’s financial instruments, as well as its level within the GAAP fair value hierarchy, as of September 30, 2016 and December 31, 2015 , respectively (in thousands): September 30, 2016 December 31, 2015 Financial Instrument Carrying Value Estimated Fair Value Level Within Fair Value Hierarchy Carrying Value Estimated Fair Value Level Within Fair Value Hierarchy Assets: Cash and cash equivalents (1) $ 6,032 $ 6,032 Level 1 $ 5,441 $ 5,441 Level 1 Tenant receivables, net (1) $ 24,785 $ 24,785 Level 1 $ 26,339 $ 26,339 Level 1 Notes receivable (1) $ — $ — Level 1 $ 45,400 $ 45,400 Level 1 Restricted cash and escrows (1) $ 5,182 $ 5,182 Level 1 $ 5,174 $ 5,174 Level 1 Liabilities: Accounts payable and accrued expenses (1) $ 17,753 $ 17,753 Level 1 $ 13,188 $ 13,188 Level 1 Interest rate swap liability $ 17,835 $ 17,835 Level 2 $ 9,993 $ 9,993 Level 2 Debt $ 1,994,078 $ 2,039,912 Level 2 $ 2,029,510 $ 2,039,139 Level 2 (1) For the periods presented, the carrying value of these financial instruments approximates estimated fair value due to their short-term maturity.

Impairment Loss on Real Estat29

Impairment Loss on Real Estate Assets Impairment Loss on Real Estate Assets (Tables)	9 Months Ended
	Sep. 30, 2016
Real Estate [Abstract]
Schedule of Impairment Loss on Real Estate Assets	Piedmont recorded impairment loss on real estate assets for the three and nine months ended September 30, 2016 and 2015 , respectively, as follows (in thousands): Three Months Ended Nine Months Ended 2016 2015 2016 2015 Eastpoint I & II (1) $ — $ — $ — $ 5,354 2 Gatehall Drive (1) — 34,815 — 34,815 150 West Jefferson (1) — — 5,972 — 9221 Corporate Boulevard (2) — — 2,336 — 9200 and 9211 Corporate Boulevard (3) 22,590 — 22,590 — Total impairment loss on real estate assets (4) $ 22,590 $ 34,815 $ 30,898 $ 40,169 (1) Piedmont recognized an impairment loss on real estate assets based upon the difference between the carrying value of the asset and the contracted sales price, less estimated selling costs. (2) Piedmont, using a probability-weighted model heavily weighted towards the short-term sale of the 9221 Corporate Boulevard building in Rockville, Maryland, determined that the carrying value would not be recovered from the undiscounted future operating cash flows expected from the use of the asset and its eventual disposition. As a result, Piedmont recognized a loss on impairment of approximately $2.3 million during the nine months ended September 30, 2016 calculated as the difference between the carrying value of the asset and the anticipated contract sales price, less estimated selling costs. (3) Piedmont elected to sell its remaining two assets and exit the Rockville, Maryland sub-market of Washington, D.C, after selling the 9221 Corporate Boulevard building in July 2016 (mentioned above). Upon management's change in its hold period assumption for the assets from a long-term hold to a near-term sale, Piedmont recognized an impairment loss of approximately $22.6 million . The impairment loss was calculated as the difference between the carrying value of the asset and the anticipated contracted sales price, less estimated selling costs. Piedmont reclassified the properties as held for sale, recognized an impairment loss, entered into a binding contract, and subsequently sold the 9200 and 9211 Corporate Boulevard buildings during the three months ended September 30, 2016. (4) The fair value measurements used in the evaluation of the non-financial assets above are considered to be Level 1 valuations within the fair value hierarchy as defined by GAAP, as there are direct observations and transactions involving the assets by unrelated, third-party purchasers. Details of amounts held for sale as of December 31, 2015 are presented below (in thousands): September 30, 2016 December 31, 2015 Real estate assets held for sale, net: Land $ — $ 9,759 Building and improvements, less accumulated depreciation of $0 and $32,162 as of September 30, 2016 and December 31, 2015, respectively — 66,840 Construction in progress — 15 Total real estate assets held for sale, net $ — $ 76,614 Other assets held for sale, net: Straight-line rent receivables $ — $ 4,729 Prepaid expenses and other assets — 66 Deferred lease costs, less accumulated amortization of $0 and $1,162 as of September 30, 2016 and December 31, 2015, respectively — 3,695 Total other assets held for sale, net $ — $ 8,490

Property Dispositions, Assets30

Property Dispositions, Assets Held for Sale, and Discontinued Operations (Tables)	9 Months Ended
	Sep. 30, 2016
Discontinued Operations and Disposal Groups [Abstract]
Schedule of Disposal Groups, Including Discontinued Operations, Income Statement, Balance Sheet and Additional Disclosures	Details comprising loss from discontinued operations activity on 1441 West Long Lake Road in Troy, Michigan, 11109 Sunset Hills Road in Reston, Virginia, and 1200 Enclave Parkway in Houston, Texas for the three and nine months ended ended September 30, 2016 and 2015 are presented below (in thousands): Three Months Ended Nine Months Ended September 30, 2016 September 30, 2015 September 30, 2016 September 30, 2015 Revenues: Rental income $ — $ 19 $ — $ 19 Tenant reimbursements — — — (3 ) — 19 — 16 Expenses: Property operating costs — 3 — 2 General and administrative (1 ) — — 1 (1 ) 3 — 3 Operating income 1 16 — 13 Loss on sale of real estate assets — (2 ) — (2 ) Income from discontinued operations $ 1 $ 14 $ — $ 11 Properties sold during the nine months ended September 30, 2016 and 2015 did not meet the criteria to be reported as discontinued operations. The operational results for these properties prior to their sale dates are presented as continuing operations in the accompanying consolidated statements of income, and the gain/(loss) on sale is presented separately on the face of the income statement. Details of such properties sold are presented below (in thousands): Buildings Sold (1) Location Date of Sale Gain/(Loss) on Sale Net Sales Proceeds 3900 Dallas Parkway Plano, Texas January 30, 2015 $ 10,073 $ 25,803 5601 Headquarters Drive Plano, Texas April 28, 2015 $ 7,959 $ 33,326 River Corporate Center Tempe, Arizona April 29, 2015 $ 5,297 $ 24,223 Copper Ridge Center Lyndhurst, New Jersey May 1, 2015 $ 13,711 $ 50,372 (2) Eastpoint I & II Mayfield Heights, Ohio July 28, 2015 $ (177 ) $ 17,342 3750 Brookside Parkway Alpharetta, Georgia August 10, 2015 $ 1,406 $ 13,624 Chandler Forum Chandler, Arizona September 1, 2015 $ 15,506 $ 32,267 1055 East Colorado Pasadena, California April 21, 2016 $ 31,501 $ 60,076 Fairway Center II Brea, California April 28, 2016 $ 15,468 $ 33,063 1901 Main Street Irvine, California May 2, 2016 $ 32,016 $ 63,149 (3) 9221 Corporate Boulevard Rockville, Maryland July 27, 2016 $ (191 ) $ 12,037 150 West Jefferson Detroit, Michigan July 29, 2016 $ 134 $ 78,642 9200 and 9211 Corporate Boulevard Rockville, Maryland September 28, 2016 $ — (4) $ 12,535 (1) The dispositions of Aon Center in Chicago, Illinois on October 29, 2015, and 2 Gatehall Drive in Parsippany, New Jersey on December 21, 2015 has impacted the comparative analysis of operating results for the three and nine months ended September 30, 2016. (2) As part of the transaction, Piedmont accepted a secured promissory note from the buyer for $45.4 million . During the nine months ended September 30, 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 part of the transaction, Piedmont accepted a secured promissory note from the buyer for $33.0 million ; however, the note receivable was repaid in full by September 30, 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. (4) As discussed in Note 8 above, Piedmont recognized an impairment loss of approximately $22.6 million during the three months ended September 30, 2016. As the sale was consummated within the same quarter, there was no gain or loss recognized upon the sale.
Disclosure of Long Lived Assets Held-for-sale	Piedmont recorded impairment loss on real estate assets for the three and nine months ended September 30, 2016 and 2015 , respectively, as follows (in thousands): Three Months Ended Nine Months Ended 2016 2015 2016 2015 Eastpoint I & II (1) $ — $ — $ — $ 5,354 2 Gatehall Drive (1) — 34,815 — 34,815 150 West Jefferson (1) — — 5,972 — 9221 Corporate Boulevard (2) — — 2,336 — 9200 and 9211 Corporate Boulevard (3) 22,590 — 22,590 — Total impairment loss on real estate assets (4) $ 22,590 $ 34,815 $ 30,898 $ 40,169 (1) Piedmont recognized an impairment loss on real estate assets based upon the difference between the carrying value of the asset and the contracted sales price, less estimated selling costs. (2) Piedmont, using a probability-weighted model heavily weighted towards the short-term sale of the 9221 Corporate Boulevard building in Rockville, Maryland, determined that the carrying value would not be recovered from the undiscounted future operating cash flows expected from the use of the asset and its eventual disposition. As a result, Piedmont recognized a loss on impairment of approximately $2.3 million during the nine months ended September 30, 2016 calculated as the difference between the carrying value of the asset and the anticipated contract sales price, less estimated selling costs. (3) Piedmont elected to sell its remaining two assets and exit the Rockville, Maryland sub-market of Washington, D.C, after selling the 9221 Corporate Boulevard building in July 2016 (mentioned above). Upon management's change in its hold period assumption for the assets from a long-term hold to a near-term sale, Piedmont recognized an impairment loss of approximately $22.6 million . The impairment loss was calculated as the difference between the carrying value of the asset and the anticipated contracted sales price, less estimated selling costs. Piedmont reclassified the properties as held for sale, recognized an impairment loss, entered into a binding contract, and subsequently sold the 9200 and 9211 Corporate Boulevard buildings during the three months ended September 30, 2016. (4) The fair value measurements used in the evaluation of the non-financial assets above are considered to be Level 1 valuations within the fair value hierarchy as defined by GAAP, as there are direct observations and transactions involving the assets by unrelated, third-party purchasers. Details of amounts held for sale as of December 31, 2015 are presented below (in thousands): September 30, 2016 December 31, 2015 Real estate assets held for sale, net: Land $ — $ 9,759 Building and improvements, less accumulated depreciation of $0 and $32,162 as of September 30, 2016 and December 31, 2015, respectively — 66,840 Construction in progress — 15 Total real estate assets held for sale, net $ — $ 76,614 Other assets held for sale, net: Straight-line rent receivables $ — $ 4,729 Prepaid expenses and other assets — 66 Deferred lease costs, less accumulated amortization of $0 and $1,162 as of September 30, 2016 and December 31, 2015, respectively — 3,695 Total other assets held for sale, net $ — $ 8,490

Stock Based Compensation (Table

Stock Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Nonvested Share Activity	A rollforward of Piedmont's equity based award activity for the nine months ended September 30, 2016 is as follows: Shares Weighted-Average Grant Date Fair Value Unvested Stock Awards as of December 31, 2015 959,446 $ 18.67 Deferred Stock Awards Granted 319,083 $ 19.96 Increase in Estimated Potential Future Performance Share Awards, net of forfeitures 115,655 $ 22.94 Performance Stock Awards Vested (53,287 ) $ 18.91 Deferred Stock Awards Vested (256,511 ) $ 18.58 Deferred Stock Awards Forfeited (17,922 ) $ 18.22 Unvested Stock Awards as of September 30, 2016 1,066,464 $ 19.67 The following table provides additional information regarding stock award activity during the three and nine months ended September 30, 2016 and 2015 , respectively (in thousands except for per share data): Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, Weighted-Average Grant Date Fair Value of Deferred Stock Granted During the Period (per share) $ — $ 18.31 $ 19.96 $ 17.59 Total Grant Date Fair Value of Deferred Stock Vested During the Period $ 108 $ 32 $ 4,766 $ 4,109 Share-based Liability Awards Paid During the Period (1) $ — $ — $ 1,127 $ — (1) Amount reflects the issuance of performance share awards related to the 2013-15 Performance Share Plan during the period.
Schedule of Outstanding Employee Stock Awards	A detail of Piedmont’s outstanding stock awards as of September 30, 2016 is as follows: Date of grant Type of Award Net Shares Granted (1) Grant Date Fair Value Vesting Schedule Unvested Shares as of September 30, 2016 January 3, 2014 Deferred Stock Award 86,512 $ 16.45 Of the shares granted, 20% vested or will vest on January 3, 2015, 2016, 2017, 2018, and 2019, respectively. 52,886 May 9, 2014 Deferred Stock Award 145,330 $ 18.46 Of the shares granted, 25% vested on the date of grant, and 25% vested or will vest on May 9, 2015, 2016, and 2017, respectively. 46,555 May 9, 2014 Fiscal Year 2014-2016 Performance Share Program — $ 22.00 Shares awarded, if any, will vest immediately upon determination of award in 2017. 155,919 (2) May 1, 2015 Deferred Stock Award 243,884 $ 17.59 Of the shares granted, 25% vested on the date of grant, and 25% vested or will vest on May 1, 2016, 2017, and 2018, respectively. 138,816 May 1, 2015 Fiscal Year 2015-2017 Performance Share Program — $ 18.42 Shares awarded, if any, will vest immediately upon determination of award in 2018. 297,424 (2) May 12, 2016 Deferred Stock Award-Board of Directors 31,368 $ 20.40 Of the shares granted, 100% will vest on May 12, 2017. 31,368 May 24, 2016 Deferred Stock Award 259,957 $ 19.91 Of the shares granted, 25% vested on the date of grant, and 25% vested or will vest on May 24, 2017, 2018, and 2019, respectively. 207,412 May 24, 2016 Fiscal Year 2016-2018 Performance Share Program — $ 23.02 Shares awarded, if any, will vest immediately upon determination of award in 2019. 136,084 (2) Total 1,066,464 (1) Amounts reflect the total grant to employees and independent directors, net of shares surrendered upon vesting to satisfy required minimum tax withholding obligations through September 30, 2016 . (2) Estimated based on Piedmont's cumulative TSR for the respective performance period through September 30, 2016 . Share estimates are subject to change in future periods based on both Piedmont's and its peers' stock performance and dividends paid.

Earnings Per Share (Tables)

Earnings Per Share (Tables)	9 Months Ended
	Sep. 30, 2016
Earnings Per Share [Abstract]
Schedule of Weighted Average Number of Shares	The following table reconciles the denominator for the basic and diluted earnings per share computations shown on the consolidated statements of income for the three and nine months ended September 30, 2016 and 2015 , respectively (in thousands): Three Months Ended Nine Months Ended September 30, 2016 September 30, 2015 September 30, 2016 September 30, 2015 Weighted-average common shares – basic 145,231 148,855 145,229 152,231 Plus incremental weighted-average shares from time-vested conversions: Deferred and performance stock awards 438 321 372 268 Weighted-average common shares – diluted (1) 145,669 149,176 145,601 152,499 (1) Due to repurchases of common stock during the current year, Piedmont has 145,233,753 shares of common stock outstanding as of September 30, 2016 .

Guarantor and Non-Guarantor F33

Guarantor and Non-Guarantor Financial Information (Tables)	9 Months Ended
	Sep. 30, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Condensed Consolidated Balance Sheets	Condensed Consolidated Balance Sheets As of September 30, 2016 (in thousands) Issuer Guarantor Non-Guarantor Subsidiaries Eliminations Consolidated Assets: Real estate assets, at cost: Land $ 48,213 $ — $ 615,484 $ — $ 663,697 Buildings and improvements, less accumulated depreciation 238,912 — 2,659,027 (300 ) 2,897,639 Intangible lease assets, less accumulated amortization 861 — 91,495 — 92,356 Construction in progress 1,136 — 33,950 — 35,086 Total real estate assets 289,122 — 3,399,956 (300 ) 3,688,778 Investments in and amounts due from unconsolidated joint ventures 7,351 — — — 7,351 Cash and cash equivalents 3,591 150 2,291 — 6,032 Tenant and straight-line rent receivables, net 20,398 — 163,198 — 183,596 Advances to affiliates 6,350,066 1,284,119 — (7,634,185 ) — Investment in subsidiary — 3,661,064 182 (3,661,246 ) — Notes receivable 88,910 — 95,790 (184,700 ) — Prepaid expenses, restricted cash, escrows, and other assets 12,148 37 23,444 (1,703 ) 33,926 Goodwill 180,097 — — — 180,097 Deferred lease costs, net 17,486 — 271,031 — 288,517 Total assets $ 6,969,169 $ 4,945,370 $ 3,955,892 $ (11,482,134 ) $ 4,388,297 Liabilities: Debt, net $ 1,675,263 $ — $ 503,515 $ (184,700 ) $ 1,994,078 Accounts payable, accrued expenses, and accrued capital expenditures 18,061 644 116,111 (1,704 ) 133,112 Advances from affiliates 659,326 5,071,498 1,998,428 (7,729,252 ) — Deferred income 6,741 — 22,265 — 29,006 Intangible lease liabilities, net — — 45,283 — 45,283 Interest rate swaps 17,835 — — — 17,835 Total liabilities 2,377,226 5,072,142 2,685,602 (7,915,656 ) 2,219,314 Stockholders’ Equity: Common stock — 1,452 — — 1,452 Additional paid-in capital 3,657,063 3,675,090 1,310 (3,661,245 ) 3,672,218 Retained/(cumulative distributions in excess of) earnings 942,091 (3,803,314 ) 1,267,082 94,767 (1,499,374 ) Other comprehensive loss (7,211 ) — — — (7,211 ) Piedmont stockholders’ equity 4,591,943 (126,772 ) 1,268,392 (3,566,478 ) 2,167,085 Noncontrolling interest — — 1,898 — 1,898 Total stockholders’ equity 4,591,943 (126,772 ) 1,270,290 (3,566,478 ) 2,168,983 Total liabilities and stockholders’ equity $ 6,969,169 $ 4,945,370 $ 3,955,892 $ (11,482,134 ) $ 4,388,297 Condensed Consolidated Balance Sheets As of December 31, 2015 (in thousands) Issuer Guarantor Non-Guarantor Subsidiaries Eliminations Consolidated Assets: Real estate assets, at cost: Land $ 54,459 $ — $ 621,632 $ — $ 676,091 Buildings and improvements, less accumulated depreciation 270,057 — 2,567,706 (300 ) 2,837,463 Intangible lease assets, less accumulated amortization 1,268 — 83,395 — 84,663 Construction in progress 240 — 20,735 — 20,975 Real estate assets held for sale, net 76,614 — — — 76,614 Total real estate assets 402,638 — 3,293,468 (300 ) 3,695,806 Investments in and amounts due from unconsolidated joint ventures 7,577 — — — 7,577 Cash and cash equivalents 2,174 150 3,117 — 5,441 Tenant and straight-line rent receivables, net 23,738 — 149,994 — 173,732 Advances to affiliates 6,073,606 1,251,530 — (7,325,136 ) — Investment in subsidiary — 3,752,523 186 (3,752,709 ) — Notes receivable 134,750 — 23,890 (113,240 ) 45,400 Prepaid expenses, restricted cash, escrows, and other assets 7,091 — 24,118 (1,258 ) 29,951 Goodwill 180,097 — — — 180,097 Deferred lease costs, net 20,939 — 267,102 — 288,041 Other assets held for sale, net 8,490 — — — 8,490 Total assets $ 6,861,100 $ 5,004,203 $ 3,761,875 $ (11,192,643 ) $ 4,434,535 Liabilities: Debt, net $ 1,552,007 $ — $ 590,743 $ (113,240 ) $ 2,029,510 Accounts payable, accrued expenses, and accrued capital expenditures 18,954 580 110,189 (1,258 ) 128,465 Advances from affiliates 580,526 5,033,266 1,788,840 (7,402,632 ) — Deferred income 5,905 — 21,365 — 27,270 Intangible lease liabilities, net — — 42,853 — 42,853 Interest rate swaps 9,993 — — — 9,993 Total liabilities 2,167,385 5,033,846 2,553,990 (7,517,130 ) 2,238,091 Stockholders’ Equity: Common stock — 1,455 — — 1,455 Additional paid-in capital 3,748,524 3,672,849 1,314 (3,752,710 ) 3,669,977 Retained/(cumulative distributions in excess of) earnings 943,530 (3,703,947 ) 1,205,546 77,197 (1,477,674 ) Other comprehensive income 1,661 — — — 1,661 Piedmont stockholders’ equity 4,693,715 (29,643 ) 1,206,860 (3,675,513 ) 2,195,419 Noncontrolling interest — — 1,025 — 1,025 Total stockholders’ equity 4,693,715 (29,643 ) 1,207,885 (3,675,513 ) 2,196,444 Total liabilities and stockholders’ equity $ 6,861,100 $ 5,004,203 $ 3,761,875 $ (11,192,643 ) $ 4,434,535
Condensed Consolidated Statements of Income	Condensed Consolidated Statements of Income For the three months ended September 30, 2016 (in thousands) Issuer Guarantor Non-Guarantor Subsidiaries Eliminations Consolidated Revenues: Rental income $ 12,862 $ — $ 101,423 $ (464 ) $ 113,821 Tenant reimbursements 3,430 — 20,970 (237 ) 24,163 Property management fee revenue — — 3,985 (3,484 ) 501 16,292 — 126,378 (4,185 ) 138,485 Expenses: Property operating costs 7,820 — 51,287 (4,240 ) 54,867 Depreciation 3,617 — 27,993 — 31,610 Amortization 863 — 17,777 — 18,640 Impairment loss on real estate assets — — 22,590 — 22,590 General and administrative 7,187 83 9,016 (8,857 ) 7,429 19,487 83 128,663 (13,097 ) 135,136 Real estate operating income/(loss) (3,195 ) (83 ) (2,285 ) 8,912 3,349 Other income (expense): Interest expense (11,799 ) — (6,949 ) 3,252 (15,496 ) Other income/(expense) 2,608 — (76 ) (3,252 ) (720 ) Recovery from casualty event — — 34 — 34 Equity in income of unconsolidated joint ventures 128 — — — 128 (9,063 ) — (6,991 ) — (16,054 ) Income/(loss) from continuing operations (12,258 ) (83 ) (9,276 ) 8,912 (12,705 ) Discontinued operations: Operating income — — 1 — 1 Income from discontinued operations — — 1 — 1 Gain/(loss) on sale of real estate assets 134 — (191 ) — (57 ) Net income/(loss) (12,124 ) (83 ) (9,466 ) 8,912 (12,761 ) Less: Net loss applicable to noncontrolling interest — — 15 — 15 Net income/(loss) applicable to Piedmont $ (12,124 ) $ (83 ) $ (9,451 ) $ 8,912 $ (12,746 ) Condensed Consolidated Statements of Income For the three months ended September 30, 2015 (in thousands) Issuer Guarantor Non-Guarantor Subsidiaries Eliminations Consolidated Revenues: Rental income $ 15,841 $ — $ 102,888 $ (735 ) $ 117,994 Tenant reimbursements 3,369 — 26,935 (31 ) 30,273 Property management fee revenue — — 4,603 (4,055 ) 548 19,210 — 134,426 (4,821 ) 148,815 Expenses: Property operating costs 9,238 — 57,446 (5,031 ) 61,653 Depreciation 4,943 — 26,256 — 31,199 Amortization 1,126 — 12,895 — 14,021 Impairment loss on real estate assets — — 34,815 — 34,815 General and administrative 8,118 71 9,506 (9,435 ) 8,260 23,425 71 140,918 (14,466 ) 149,948 Real estate operating income/(loss) (4,215 ) (71 ) (6,492 ) 9,645 (1,133 ) Other income (expense): Interest expense (12,963 ) — (8,413 ) 2,544 (18,832 ) Other income/(expense) 3,199 — 148 (2,544 ) 803 Equity in income of unconsolidated joint ventures 135 — — — 135 (9,629 ) — (8,265 ) — (17,894 ) Income/(loss) from continuing operations (13,844 ) (71 ) (14,757 ) 9,645 (19,027 ) Discontinued operations: Operating income 16 — — — 16 Loss on sale of real estate assets (2 ) — — — (2 ) Income from discontinued operations 14 — — — 14 Gain on sale of real estate assets 17,142 — — — 17,142 Net income/(loss) 3,312 (71 ) (14,757 ) 9,645 (1,871 ) Less: Net income applicable to noncontrolling interest — — (4 ) — (4 ) Net income/(loss) applicable to Piedmont $ 3,312 $ (71 ) $ (14,761 ) $ 9,645 $ (1,875 ) Condensed Consolidated Statements of Income For the nine months ended September 30, 2016 (in thousands) Issuer Guarantor Non-Guarantor Subsidiaries Eliminations Consolidated Revenues: Rental income $ 42,990 $ — $ 299,319 $ (1,983 ) $ 340,326 Tenant reimbursements 10,455 — 59,950 (405 ) 70,000 Property management fee revenue — — 12,480 (11,002 ) 1,478 53,445 — 371,749 (13,390 ) 411,804 Expenses: Property operating costs 24,583 — 150,369 (13,514 ) 161,438 Depreciation 12,993 — 81,955 — 94,948 Amortization 2,854 — 50,994 — 53,848 Impairment loss on real estate assets 5,972 — 24,926 — 30,898 General and administrative 22,802 251 28,881 (28,416 ) 23,518 69,204 251 337,125 (41,930 ) 364,650 Real estate operating income/(loss) (15,759 ) (251 ) 34,624 28,540 47,154 Other income (expense): Interest expense (36,159 ) — (20,354 ) 8,219 (48,294 ) Other income/(expense) 7,008 282 462 (8,219 ) (467 ) Recovery from casualty event — — 34 — 34 Equity in income of unconsolidated joint ventures 354 — — — 354 (28,797 ) 282 (19,858 ) — (48,373 ) Income/(loss) from continuing operations (44,556 ) 31 14,766 28,540 (1,219 ) Gain on sale of real estate assets, net 32,146 — 46,764 — 78,910 Net income/(loss) (12,410 ) 31 61,530 28,540 77,691 Less: Net loss applicable to noncontrolling interest — — 7 — 7 Net income/(loss) applicable to Piedmont $ (12,410 ) $ 31 $ 61,537 $ 28,540 $ 77,698 Condensed Consolidated Statements of Income For the nine months ended September 30, 2015 (in thousands) Issuer Guarantor Non-Guarantor Subsidiaries Eliminations Consolidated Revenues: Rental income $ 51,824 $ — $ 303,603 $ (2,172 ) $ 353,255 Tenant reimbursements 11,171 — 79,634 (329 ) 90,476 Property management fee revenue — — 13,543 (11,966 ) 1,577 62,995 — 396,780 (14,467 ) 445,308 Expenses: Property operating costs 29,459 — 172,977 (15,068 ) 187,368 Depreciation 15,904 — 87,566 — 103,470 Amortization 3,477 — 40,169 — 43,646 Impairment loss of real estate assets 5,354 — 34,815 — 40,169 General and administrative 22,211 266 26,504 (26,231 ) 22,750 76,405 266 362,031 (41,299 ) 397,403 Real estate operating income/(loss) (13,410 ) (266 ) 34,749 26,832 47,905 Other income (expense): Interest expense (39,592 ) — (25,130 ) 8,702 (56,020 ) Other income/(expense) 9,357 — 563 (8,702 ) 1,218 Equity in income of unconsolidated joint ventures 418 — — — 418 (29,817 ) — (24,567 ) — (54,384 ) Income/(loss) from continuing operations (43,227 ) (266 ) 10,182 26,832 (6,479 ) Discontinued operations: Operating income 13 — — — 13 Loss on sale of real estate assets (2 ) — — — (2 ) Income from discontinued operations 11 — — — 11 Gain on sale of real estate assets, net 53,826 — — — 53,826 Net income/(loss) 10,610 (266 ) 10,182 26,832 47,358 Less: Net income applicable to noncontrolling interest — — (12 ) — (12 ) Net income/(loss) applicable to Piedmont $ 10,610 $ (266 ) $ 10,170 $ 26,832 $ 47,346
Condensed Consolidated Statements of Cash Flows	Condensed Consolidated Statements of Cash Flows For the nine months ended September 30, 2016 (in thousands) Issuer Guarantor Non-Guarantor Subsidiaries Eliminations Consolidated Net Cash Provided by Operating Activities $ (18,977 ) $ 4,121 $ 158,352 $ 28,540 $ 172,036 Cash Flows from Investing Activities: Investment in real estate assets, consolidated joint venture, and real estate related intangibles, net of accruals (24,255 ) — (296,884 ) — (321,139 ) Intercompany note receivable 440 — (71,900 ) 71,460 — Net sales proceeds from wholly-owned properties 187,192 — 117,710 — 304,902 Deferred lease costs paid (2,021 ) — (13,324 ) — (15,345 ) Net cash provided by/(used in) investing activities 161,356 — (264,398 ) 71,460 (31,582 ) Cash Flows from Financing Activities: Debt issuance costs paid (212 ) — — — (212 ) Proceeds from debt 552,000 — — — 552,000 Repayments of debt (421,000 ) — (168,532 ) — (589,532 ) Intercompany note payable (9,600 ) — 81,060 (71,460 ) — Costs of issuance of common stock — (239 ) — — (239 ) Shares withheld to pay tax obligations related to employee stock compensation — (2,328 ) — — (2,328 ) Repurchases of common stock as part of announced plan — (7,943 ) — — (7,943 ) (Distributions to)/repayments from affiliates (262,150 ) 97,990 192,700 (28,540 ) — Dividends paid and discount on dividend reinvestments — (91,601 ) (8 ) — (91,609 ) Net cash provided by/(used in) financing activities (140,962 ) (4,121 ) 105,220 (100,000 ) (139,863 ) Net increase/(decrease) in cash and cash equivalents 1,417 — (826 ) — 591 Cash and cash equivalents, beginning of period 2,174 150 3,117 — 5,441 Cash and cash equivalents, end of period $ 3,591 $ 150 $ 2,291 $ — $ 6,032 Condensed Consolidated Statements of Cash Flows For the nine months ended September 30, 2015 (in thousands) Issuer Guarantor Non-Guarantor Subsidiaries Eliminations Consolidated Net Cash Provided by Operating Activities $ (41,584 ) $ 3,772 $ 145,240 $ 26,833 $ 134,261 Cash Flows from Investing Activities: Investment in real estate assets and real estate related intangibles, net of accruals (28,249 ) — (129,644 ) — (157,893 ) Intercompany note receivable 72,000 — — (72,000 ) — Redemption of noncontrolling interest in unconsolidated variable interest entity — — (4,000 ) — (4,000 ) Net sales proceeds from wholly-owned properties 151,564 — — — 151,564 Deferred lease costs paid (2,577 ) — (21,312 ) — (23,889 ) Net cash provided by/(used in) investing activities 192,738 — (154,956 ) (72,000 ) (34,218 ) Cash Flows from Financing Activities: Debt issuance costs paid (545 ) — (503 ) — (1,048 ) Proceeds from debt 1,046,578 — 159,279 — 1,205,857 Repayments of debt (950,000 ) — (177,902 ) 72,000 (1,055,902 ) Costs of issuance of common stock — (326 ) — — (326 ) Shares withheld to pay tax obligations related to employee stock compensation — (1,665 ) — — (1,665 ) Repurchases of common stock as part of announced plan — (155,653 ) — — (155,653 ) (Distributions to)/repayments from affiliates (251,395 ) 248,135 30,093 (26,833 ) — Dividends paid and discount on dividend reinvestments — (95,902 ) (8 ) — (95,910 ) Net cash provided/(used in) by financing activities (155,362 ) (5,411 ) 10,959 45,167 (104,647 ) Net increase/(decrease) in cash and cash equivalents (4,208 ) (1,639 ) 1,243 — (4,604 ) Cash and cash equivalents, beginning of period 8,143 1,790 2,373 — 12,306 Cash and cash equivalents, end of period $ 3,935 $ 151 $ 3,616 $ — $ 7,702

Organization (Details)

Organization (Details) ft² in Millions	9 Months Ended
	Sep. 30, 2016ft²segmentpropertysubsidiaryredevelopment_asset
Real Estate Properties [Line Items]
Number of wholly-owned subsidiaries | subsidiary	2
Percentage ownership by sole general partner	99.90%
Percentage ownership by sole limited partner	0.10%
Percentage of annualized lease revenue	87.00%
Number of operating segments | segment	1
Unconsolidated Joint Venture [Member]
Real Estate Properties [Line Items]
Number of real estate properties	1
Office properties [Member]
Real Estate Properties [Line Items]
Number of real estate properties	65
Number of redevelopment assets | redevelopment_asset	1
Number of office properties under development	2
Square footage of real estate property | ft²	18.4
Percentage leased	93.40%

Summary of Significant Accoun35

Summary of Significant Accounting Policies (Tenant Receivables, net and Straight-line Rent Receivables) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Provisions for bad debts	$ 190
Reclassification Adjustment [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Provisions for bad debts			$ 100
Recoveries of bad debts		$ (20)		$ (20)

Summary of Significant Accoun36

Summary of Significant Accounting Policies (Accounting Pronouncements Adopted and Other Recent Accounting Pronouncements) (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
New Accounting Pronouncement, Early Adoption [Line Items]
Reclassification of share-based payment transactions cash outflows from operating activities to cash outflows from financing activities	$ 2,328	$ 1,665
New Accounting Pronouncement, Early Adoption, Effect [Member] | ASU 2016-09 [Member]
New Accounting Pronouncement, Early Adoption [Line Items]
Reclassification of share-based payment transactions cash outflows from operating activities to cash outflows from financing activities		$ 1,700

Acquisitions (Details)

Acquisitions (Details)	Aug. 10, 2016USD ($)ft²building	Aug. 01, 2016USD ($)ft²building	Sep. 30, 2016USD ($)
One Wayside Road [Member]
Business Acquisition [Line Items]
Number of properties acquired | building	1
Ownership Percentage Acquired	100.00%
Rentable Square Feet (Unaudited) | ft²	200,605
Percentage Leased as of Acquisition (Unaudited)	100.00%
Net Contractual Purchase Price (in millions)	$ 62,900,000
CNL Tower I and II [Member]
Business Acquisition [Line Items]
Number of properties acquired | building		2
Ownership Percentage Acquired		99.00%
Rentable Square Feet (Unaudited) | ft²		622,488
Percentage Leased as of Acquisition (Unaudited)		95.00%
Net Contractual Purchase Price (in millions)		$ 166,700,000
$500 Million Unsecured 2015 Line of Credit [Member] | Line of Credit [Member] | Unsecured Debt [Member]
Business Acquisition [Line Items]
Amount of line of credit			$ 500,000,000

Debt (Narrative) (Details)

Debt (Narrative) (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Debt Instrument [Line Items]
Interest payments on debt facilities	$ 18,500,000	$ 20,100,000	$ 53,200,000	$ 58,800,000
Capitalized interest	1,500,000	$ 1,000,000	3,400,000	$ 2,700,000
Secured Debt [Member] | $125 Million Fixed Rate Loan [Member]
Debt Instrument [Line Items]
Amount repaid			125,000,000
Secured Debt [Member] | $42.5 Million Fixed Rate Loan [Member]
Debt Instrument [Line Items]
Amount repaid			42,500,000
Line of Credit [Member] | Unsecured Debt [Member] | $500 Million Unsecured 2015 Line of Credit [Member]
Debt Instrument [Line Items]
Net borrowings incurred			131,000,000
Amount of line of credit	$ 500,000,000		$ 500,000,000

Debt (Details)

Debt (Details)		9 Months Ended
		Sep. 30, 2016USD ($)period	Nov. 22, 2016	Dec. 31, 2015USD ($)
Debt Instrument [Line Items]
Weighted Average Rate	[1],[2],[3]	3.28%
Amount Outstanding	[2],[3]	$ 1,994,078,000		$ 2,029,510,000
Secured Debt [Member]
Debt Instrument [Line Items]
Weighted Average Rate	[1],[2],[3]	4.64%
Amount Outstanding	[2],[3]	$ 333,012,000		501,289,000
Net premium, discounts, and unamortized debt issuance costs	[2]	1,210,000		1,319,000
Secured Debt [Member] | $125 Million Fixed Rate Loan [Member]
Debt Instrument [Line Items]
Face amount of debt instrument	[2]	$ 125,000,000
Stated Rate	[2]	5.50%
Effective interest rate	[1],[2]	5.50%
Amount Outstanding	[2]	$ 0		125,000,000
Secured Debt [Member] | $42.5 Million Fixed Rate Loan [Member]
Debt Instrument [Line Items]
Face amount of debt instrument	[2]	$ 42,500,000
Stated Rate	[2]	5.70%
Effective interest rate	[1],[2]	5.70%
Amount Outstanding	[2]	$ 0		42,525,000
Secured Debt [Member] | $140 Million WDC Fixed Rate Loans [Member]
Debt Instrument [Line Items]
Face amount of debt instrument	[2],[4]	$ 140,000,000
Stated Rate	[2],[4]	5.76%
Effective interest rate	[1],[2],[4]	5.76%
Amount Outstanding	[2],[4]	$ 140,000,000		140,000,000
Secured Debt [Member] | $35 Million Fixed-Rate Loan [Member]
Debt Instrument [Line Items]
Face amount of debt instrument	[2],[5]	$ 35,000,000
Stated Rate	[2],[5]	5.55%
Effective interest rate	[1],[2],[5]	3.75%
Amount Outstanding	[2],[5]	$ 31,802,000		32,445,000
Secured Debt [Member] | $160 Million Fixed Rate Loan [Member]
Debt Instrument [Line Items]
Face amount of debt instrument	[2],[6]	$ 160,000,000
Stated Rate	[2],[6]	3.48%
Effective interest rate	[1],[2],[6]	3.58%
Amount Outstanding	[2],[6]	$ 160,000,000		160,000,000
Unsecured Debt [Member]
Debt Instrument [Line Items]
Weighted Average Rate	[1],[2],[3]	3.01%
Amount Outstanding	[2],[3]	$ 1,661,066,000		1,528,221,000
Net premium, discounts, and unamortized debt issuance costs	[2]	(10,934,000)		(12,779,000)
Unsecured Debt [Member] | $170 Million Unsecured 2015 Term Loan [Member]
Debt Instrument [Line Items]
Face amount of debt instrument	[2],[7]	$ 170,000,000
Effective interest rate	[1],[2],[7]	1.66%
Amount Outstanding	[2],[7]	$ 170,000,000		170,000,000
Unsecured Debt [Member] | $170 Million Unsecured 2015 Term Loan [Member] | London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	[2],[7]	1.125%
Unsecured Debt [Member] | $300 million Unsecured 2013 Term Loan [Member]
Debt Instrument [Line Items]
Face amount of debt instrument	[2]	$ 300,000,000
Amount Outstanding	[2]	$ 300,000,000		300,000,000
Unsecured Debt [Member] | $300 million Unsecured 2013 Term Loan [Member] | Interest Rate Swap [Member]
Debt Instrument [Line Items]
Effective interest rate	[1],[2]	2.78%
Unsecured Debt [Member] | $300 million Unsecured 2013 Term Loan [Member] | London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	[2]	1.20%
Unsecured Debt [Member] | $500 Million Unsecured 2015 Line of Credit [Member] | Line of Credit [Member]
Debt Instrument [Line Items]
Face amount of debt instrument	[2],[7]	$ 500,000,000
Effective interest rate	[1],[2],[7]	1.53%
Amount Outstanding	[2],[7],[8]	$ 152,000,000		21,000,000
Maximum extension period		1 year
Number of extension periods | period		2
Extension period		6 months
Unsecured Debt [Member] | $500 Million Unsecured 2015 Line of Credit [Member] | Line of Credit [Member] | London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	[2],[7]	1.00%
Unsecured Debt [Member] | $300 Million Unsecured 2011 Term Loan [Member]
Debt Instrument [Line Items]
Face amount of debt instrument	[2],[9]	$ 300,000,000
Amount Outstanding	[2],[9]	$ 300,000,000		300,000,000
Unsecured Debt [Member] | $300 Million Unsecured 2011 Term Loan [Member] | Interest Rate Swap [Member]
Debt Instrument [Line Items]
Effective interest rate	[1],[2],[9]	2.39%
Unsecured Debt [Member] | $300 Million Unsecured 2011 Term Loan [Member] | Interest Rate Swap [Member] | Scenario, Forecast [Member]
Debt Instrument [Line Items]
Effective interest rate			3.35%
Unsecured Debt [Member] | $300 Million Unsecured 2011 Term Loan [Member] | London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	[2],[9]	1.15%
Unsecured Debt [Member] | $350 Million Unsecured Senior Notes [Member]
Debt Instrument [Line Items]
Face amount of debt instrument	[2]	$ 350,000,000
Stated Rate	[2]	3.40%
Effective interest rate	[1],[2]	3.43%
Amount Outstanding	[2]	$ 350,000,000		350,000,000
Unsecured Debt [Member] | $400 Million Unsecured Senior Notes [Member]
Debt Instrument [Line Items]
Face amount of debt instrument	[2]	$ 400,000,000
Stated Rate	[2]	4.45%
Effective interest rate	[1],[2]	4.10%
Amount Outstanding	[2]	$ 400,000,000		$ 400,000,000
[1]	Effective rate after consideration of settled or in place interest rate swap agreements and/or issuance premiums or discounts.
[2]	Other than the $35 Million Fixed-Rate Loan, all of Piedmont’s outstanding debt as of September 30, 2016 and December 31, 2015 is interest-only.
[3]	Weighted average is based on contractual balance of outstanding debt and the stated or effectively fixed interest rates in the table as of September 30, 2016.
[4]	Collateralized by the 1201 and 1225 Eye Street buildings in Washington, D.C.
[5]	Collateralized by the 5 Wall Street building in Burlington, Massachusetts.
[6]	Collateralized by the 1901 Market Street building in Philadelphia, Pennsylvania.
[7]	On a periodic basis, Piedmont may select from multiple interest rate options, including the prime rate and various-length LIBOR locks. All LIBOR selections are subject to an additional spread over the selected rate based on Piedmont’s current credit rating.
[8]	Piedmont may extend the term for up to one additional year (through two available six month extensions to a final extended maturity date of June 18, 2020) provided Piedmont is not then in default and upon payment of extension fees.
[9]	The $300 Million Unsecured 2011 Term Loan has a stated variable rate; however, Piedmont has entered into interest rate swap agreements which effectively fix, exclusive of changes to Piedmont's credit rating, the rate on this facility to 2.39% through the original maturity date of November 22, 2016 and 3.35% from November 22, 2016 to January 15, 2020.

Variable Interest Entities (Det

Variable Interest Entities (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2016	Dec. 31, 2015
Eye Street 1201 N.W. Associates LLC [Member]
Variable Interest Entity [Line Items]
Piedmont’s % Ownership of Entity	49.50%
Net Carrying Amount	$ (7.1)	$ (7.4)
Variable interest entity, percentage of cash flow and economic benefits	100.00%
Eye Street 1225 N.W. Associates LLC [Member]
Variable Interest Entity [Line Items]
Piedmont’s % Ownership of Entity	49.50%
Net Carrying Amount	$ 9.9	3.8
Variable interest entity, percentage of cash flow and economic benefits	100.00%
Piedmont 500 W. Monroe Fee LLC [Member]
Variable Interest Entity [Line Items]
Piedmont’s % Ownership of Entity	100.00%
Net Carrying Amount	$ 263.1	$ 251.4
Variable interest entity, percentage of cash flow and economic benefits	100.00%

Derivative Instruments (Details

Derivative Instruments (Details)		3 Months Ended		9 Months Ended
		Sep. 30, 2016USD ($)contract	Sep. 30, 2015USD ($)	Sep. 30, 2016USD ($)contract	Sep. 30, 2015USD ($)	Dec. 31, 2015USD ($)
Derivative [Line Items]
Maximum period of extension term				39 months
Interest Rate Cash Flow Hedge Derivative at Fair Value, Net [Abstract]
Gross derivative assets		$ 0		$ 0		$ 0
Interest rate swaps		17,835,000		17,835,000		9,993,000
Net derivative liability		17,835,000		17,835,000		$ 9,993,000
Loss to be reclassified from accumulated other comprehensive loss to interest expense over next twelve months		5,400,000		5,400,000
Loss related to hedge ineffectiveness and terminations of cash flow hedges		0	$ 0	0	$ 0
Interest Rate Swap [Member]
Derivative [Line Items]
Total notional value		900,000,000		900,000,000
Interest Rate Swap [Member] | Interest Expense [Member]
Interest Rate Cash Flow Hedge Derivative at Fair Value, Net [Abstract]
Amount of gain/(loss) recognized in OCI on derivative		2,847,000	(22,263,000)	(12,182,000)	(21,389,000)
Amount of previously recorded loss reclassified from accumulated OCI into interest expense		1,045,000	$ 1,506,000	3,291,000	$ 4,575,000
Credit Risk Contract [Member]
Interest Rate Cash Flow Hedge Derivative at Fair Value, Net [Abstract]
Assets needed for immediate settlement, aggregate fair value		$ 18,200,000		$ 18,200,000
Unsecured Debt [Member] | $300 Million Unsecured 2011 Term Loan Maturing 2016 [Member] | Interest Rate Swap 1 through 4 [Member]
Derivative [Line Items]
Number of Swap Agreements | contract		4		4
Total notional value		$ 300,000,000		$ 300,000,000
Unsecured Debt [Member] | $300 million Unsecured 2013 Term Loan [Member]
Derivative [Line Items]
Face amount of debt instrument	[1]	$ 300,000,000		$ 300,000,000
Unsecured Debt [Member] | $300 million Unsecured 2013 Term Loan [Member] | Interest Rate Swap 5 through 8 [Member]
Derivative [Line Items]
Number of Swap Agreements | contract		4		4
Total notional value		$ 200,000,000		$ 200,000,000
Unsecured Debt [Member] | $300 million Unsecured 2013 Term Loan [Member] | Interest Rate Swap 9 through 10 [Member]
Derivative [Line Items]
Number of Swap Agreements | contract		2		2
Total notional value		$ 100,000,000		$ 100,000,000
Unsecured Debt [Member] | $300 Million Unsecured 2011 Term Loan [Member]
Derivative [Line Items]
Face amount of debt instrument	[1],[2]	$ 300,000,000		$ 300,000,000
Unsecured Debt [Member] | $300 Million Unsecured 2011 Term Loan [Member] | Forward Starting Interest Rate Swap 1 through 3 [Member]
Derivative [Line Items]
Number of Swap Agreements | contract		3		3
Total notional value		$ 300,000,000		$ 300,000,000
[1]	Other than the $35 Million Fixed-Rate Loan, all of Piedmont’s outstanding debt as of September 30, 2016 and December 31, 2015 is interest-only.
[2]	The $300 Million Unsecured 2011 Term Loan has a stated variable rate; however, Piedmont has entered into interest rate swap agreements which effectively fix, exclusive of changes to Piedmont's credit rating, the rate on this facility to 2.39% through the original maturity date of November 22, 2016 and 3.35% from November 22, 2016 to January 15, 2020.

Fair Value Measurement of Fin42

Fair Value Measurement of Financial Instruments (Details) - USD ($) $ in Thousands		Sep. 30, 2016	Dec. 31, 2015
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap liability		$ 17,835	$ 9,993
Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	[1]	6,032	5,441
Restricted cash and escrows	[1]	5,182	5,174
Accounts payable and accrued expenses	[1]	17,753	13,188
Debt		1,994,078	2,029,510
Interest Rate Swap [Member] | Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap liability		17,835	9,993
Tenant receivables, net [Member] | Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Receivables	[1]	24,785	26,339
Notes receivable [Member] | Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Receivables	[1]	0	45,400
Level 1 [Member] | Estimated Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	[1]	6,032	5,441
Restricted cash and escrows	[1]	5,182	5,174
Accounts payable and accrued expenses	[1]	17,753	13,188
Level 1 [Member] | Tenant receivables, net [Member] | Estimated Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Receivables	[1]	24,785	26,339
Level 1 [Member] | Notes receivable [Member] | Estimated Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Receivables	[1]	0	45,400
Level 2 [Member] | Estimated Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt		2,039,912	2,039,139
Level 2 [Member] | Interest Rate Swap [Member] | Estimated Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap liability		$ 17,835	$ 9,993
[1]	For the periods presented, the carrying value of these financial instruments approximates estimated fair value due to their short-term maturity.

Impairment Loss on Real Estat43

Impairment Loss on Real Estate Assets (Details) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2016USD ($)	Sep. 30, 2015USD ($)	Sep. 30, 2016USD ($)	Sep. 30, 2015USD ($)	Jul. 31, 2016property
Real Estate [Line Items]
Total impairment loss on real estate assets	[1]	$ 22,590	$ 34,815	$ 30,898	$ 40,169
Disposal Group, Held-for-sale, Not Discontinued Operations [Member] | Eastpoint I & II [Member]
Real Estate [Line Items]
Total impairment loss on real estate assets	[2]	0	0	0	5,354
Disposal Group, Held-for-sale, Not Discontinued Operations [Member] | 2 Gatehall Drive [Member]
Real Estate [Line Items]
Total impairment loss on real estate assets	[2]	0	34,815	0	34,815
Disposal Group, Held-for-sale, Not Discontinued Operations [Member] | 150 West Jefferson [Member]
Real Estate [Line Items]
Total impairment loss on real estate assets	[2]	0	0	5,972	0
Disposal Group, Held-for-sale, Not Discontinued Operations [Member] | 9200 and 9211 Corporate Boulevard [Member]
Real Estate [Line Items]
Total impairment loss on real estate assets	[3]	22,590	0	22,590	0
Number of assets sold | property						2
Recognized impairment loss on real estate assets held for sale		22,600
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | 9221 Corporate Boulevard [Member]
Real Estate [Line Items]
Total impairment loss on real estate assets	[4]	$ 0	$ 0	2,336	$ 0
Loss on impairment				$ 2,300
[1]	The fair value measurements used in the evaluation of the non-financial assets above are considered to be Level 1 valuations within the fair value hierarchy as defined by GAAP, as there are direct observations and transactions involving the assets by unrelated, third-party purchasers.
[2]	Piedmont recognized an impairment loss on real estate assets based upon the difference between the carrying value of the asset and the contracted sales price, less estimated selling costs.
[3]	Piedmont elected to sell its remaining two assets and exit the Rockville, Maryland sub-market of Washington, D.C, after selling the 9221 Corporate Boulevard building in July 2016 (mentioned above). Upon management's change in its hold period assumption for the assets from a long-term hold to a near-term sale, Piedmont recognized an impairment loss of approximately $22.6 million. The impairment loss was calculated as the difference between the carrying value of the asset and the anticipated contracted sales price, less estimated selling costs. Piedmont reclassified the properties as held for sale, recognized an impairment loss, entered into a binding contract, and subsequently sold the 9200 and 9211 Corporate Boulevard buildings during the three months ended September 30, 2016.
[4]	Piedmont, using a probability-weighted model heavily weighted towards the short-term sale of the 9221 Corporate Boulevard building in Rockville, Maryland, determined that the carrying value would not be recovered from the undiscounted future operating cash flows expected from the use of the asset and its eventual disposition. As a result, Piedmont recognized a loss on impairment of approximately $2.3 million during the nine months ended September 30, 2016 calculated as the difference between the carrying value of the asset and the anticipated contract sales price, less estimated selling costs.

Commitments and Contingencies (

Commitments and Contingencies (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2016USD ($)categorytenant	Sep. 30, 2015USD ($)	Sep. 30, 2016USD ($)categorytenant	Sep. 30, 2015USD ($)
Loss Contingencies [Line Items]
Number of tenant and building improvement categories | category	2		2
Collectibility of Tenant Reimbursements [Member]
Loss Contingencies [Line Items]
Reductions in reimbursement revenues	$ 0	$ 0	$ 0	$ 100,000
Tenant Audits and Disputes [Member] | Pending Litigation [Member]
Loss Contingencies [Line Items]
Number of tenants | tenant	1		1
Tenant Audits and Disputes [Member] | Pending Litigation [Member] | Minimum [Member]
Loss Contingencies [Line Items]
Amount of potential loss	$ 0		$ 0
Tenant Audits and Disputes [Member] | Pending Litigation [Member] | Maximum [Member]
Loss Contingencies [Line Items]
Amount of potential loss	1,800,000		$ 1,800,000
Non-Incremental Capital Expenditures [Member]
Loss Contingencies [Line Items]
Period for commitments for funding non-incremental capital expenditures			3 years
Potential obligations for tenant improvements	37,700,000		$ 37,700,000
Non-Incremental Capital Expenditures [Member] | Maximum [Member]
Loss Contingencies [Line Items]
Period for commitments for funding non-incremental capital expenditures			5 years
Incremental Capital Expenditures [Member]
Loss Contingencies [Line Items]
Potential obligations for tenant improvements	$ 31,300,000		$ 31,300,000

Property Dispositions, Assets45

Property Dispositions, Assets Held for Sale, and Discontinued Operations (Schedule of Property Dispositions) (Details) - USD ($) $ in Thousands

Sep. 28, 2016

Jul. 29, 2016

Jul. 27, 2016

May 02, 2016

Apr. 28, 2016

Apr. 21, 2016

Sep. 01, 2015

Aug. 10, 2015

Jul. 28, 2015

May 01, 2015

Apr. 29, 2015

Apr. 28, 2015

Jan. 30, 2015

Sep. 30, 2016

Sep. 30, 2016

Sep. 30, 2015

Dec. 31, 2015

Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]

Net Sales Proceeds

$ 304,902

$ 151,564

Note receivable

$ 0

$ 0

$ 45,400

3900 Dallas Parkway [Member] | Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]

Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]

Gain/(Loss) on Sale

[1]

$ 10,073

Net Sales Proceeds

[1]

$ 25,803

5601 Headquarters Drive [Member] | Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]

Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]

Gain/(Loss) on Sale

[1]

$ 7,959

Net Sales Proceeds

[1]

$ 33,326

River Corporate Center [Member] | Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]

Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]

Gain/(Loss) on Sale

[1]

$ 5,297

Net Sales Proceeds

[1]

$ 24,223

Copper Ridge Center [Member] | Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]

Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]

Gain/(Loss) on Sale

[1],[2]

$ 13,711

Net Sales Proceeds

[1],[2]

50,372

Copper Ridge Center [Member] | Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | Notes receivable [Member] | Secured Promissory Note [Member]

Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]

Note receivable

$ 45,400

Eastpoint I & II [Member] | Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]

Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]

Gain/(Loss) on Sale

[1]

$ (177)

Net Sales Proceeds

[1]

$ 17,342

3750 Brookside Parkway [Member] | Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]

Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]

Gain/(Loss) on Sale

[1]

$ 1,406

Net Sales Proceeds

[1]

$ 13,624

Chandler Forum [Member] | Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]

Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]

Gain/(Loss) on Sale

[1]

$ 15,506

Net Sales Proceeds

[1]

$ 32,267

1055 East Colorado [Member] | Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]

Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]

Gain/(Loss) on Sale

[1]

$ 31,501

Net Sales Proceeds

[1]

$ 60,076

Fairway Center II [Member] | Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]

Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]

Gain/(Loss) on Sale

[1]

$ 15,468

Net Sales Proceeds

[1]

$ 33,063

1901 Main Street [Member] | Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]

Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]

Gain/(Loss) on Sale

[1],[3]

$ 32,016

Net Sales Proceeds

[1],[3]

63,149

1901 Main Street [Member] | Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | Notes receivable [Member] | Secured Promissory Note [Member]

Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]

Note receivable

$ 33,000

9221 Corporate Boulevard [Member] | Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]

Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]

Gain/(Loss) on Sale

[1]

$ (191)

Net Sales Proceeds

[1]

$ 12,037

150 West Jefferson [Member] | Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]

Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]

Gain/(Loss) on Sale

[1]

$ 134

Net Sales Proceeds

[1]

$ 78,642

9200 and 9211 Corporate Boulevard [Member] | Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]

Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]

Gain/(Loss) on Sale

[1],[4]

$ 0

Net Sales Proceeds

[1]

$ 12,535

9200 and 9211 Corporate Boulevard [Member] | Disposal Group, Held-for-sale, Not Discontinued Operations [Member]

Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]

Recognized impairment loss on real estate assets held for sale

$ 22,600

[1]

The dispositions of Aon Center in Chicago, Illinois on October 29, 2015, and 2 Gatehall Drive in Parsippany, New Jersey on December 21, 2015 has impacted the comparative analysis of operating results for the three and nine months ended September 30, 2016.

[2]

As part of the transaction, Piedmont accepted a secured promissory note from the buyer for $45.4 million. During the nine months ended September 30, 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 part of the transaction, Piedmont accepted a secured promissory note from the buyer for $33.0 million; however, the note receivable was repaid in full by September 30, 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.

[4]

As discussed in Note 8 above, Piedmont recognized an impairment loss of approximately $22.6 million during the three months ended September 30, 2016. As the sale was consummated within the same quarter, there was no gain or loss recognized upon the sale.

Property Dispositions, Assets46

Property Dispositions, Assets Held for Sale, and Discontinued Operations (Schedule of Assets Held for Sale) (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Other assets held for sale, net	$ 0	$ 8,490
Disposal Group, Held-for-sale, Not Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total real estate assets held for sale, net	0	76,614
Straight-line rent receivables	0	4,729
Prepaid expenses and other assets	0	66
Deferred lease costs, less accumulated amortization of $0 and $1,162 as of September 30, 2016 and December 31, 2015, respectively	0	3,695
Other assets held for sale, net	0	8,490
Accumulated amortization on deferred lease costs	0	1,162
Disposal Group, Held-for-sale, Not Discontinued Operations [Member] | Land [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Real estate assets held for sale, net:	0	9,759
Disposal Group, Held-for-sale, Not Discontinued Operations [Member] | Building and improvements Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Real estate assets held for sale, net:	0	66,840
Accumulated depreciation and amortization	0	32,162
Disposal Group, Held-for-sale, Not Discontinued Operations [Member] | Construction in progress [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Real estate assets held for sale, net:	$ 0	$ 15

Property Dispositions, Assets47

Property Dispositions, Assets Held for Sale, and Discontinued Operations (Schedule of Discontinued Operations) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Other income/(expense)
Operating income	$ 1	$ 16	$ 0	$ 13
Loss on sale of real estate assets	0	(2)	0	(2)
Income from discontinued operations	1	14	0	11
Discontinued Operations [Member]
Revenues:
Rental income	0	19	0	19
Tenant reimbursements	0	0	0	(3)
Revenue	0	19	0	16
Expenses:
Property operating costs	0	3	0	2
General and administrative	(1)	0	0	1
Expenses	(1)	3	0	3
Other income/(expense)
Operating income	1	16	0	13
Loss on sale of real estate assets	0	(2)	0		$ (2)
Income from discontinued operations	$ 1	$ 14	$ 0	$ 11

Stock Based Compensation (Narra

Stock Based Compensation (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense related to stock awards	$ 2	$ 2.6	$ 7.7	$ 6.8
Amortization of unvested shares			$ 6.2	$ 5
Total shares issued to employees, directors, and officers			183,609
Unrecognized compensation cost related to nonvested	$ 5		$ 5
Stock Awards [Member] | Independent Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			1 year
Weighted Average [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to nonvested, weighted-average vesting period (in years)			1 year

Stock Based Compensation (Rollf

Stock Based Compensation (Rollforward of Stock Awards) (Details) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Unvested Stock Awards, Beginning of period (in shares)			959,446
Unvested Stock Awards, End of period (in shares)	1,066,464		1,066,464
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Unvested Stock Awards, Weighted-Average Grant Date Fair Value, Beginning of period (in dollars per share)			$ 18.67
Unvested Stock Awards, Weighted-Average Grant Date Fair Value, End of period (in dollars per share)	$ 19.67		$ 19.67
Performance Share Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Increase in Estimated Potential Future Performance Share Awards, net of forfeitures (in shares)			115,655
Performance Stock Awards and Deferred Stock Awards Vested (in shares)			(53,287)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Increase in Estimated Potential Future Performance Share Awards, net of forfeitures, Weighted-Average Grant Date Fair Value (in dollars per share)			$ 22.94
Performance Stock Awards and Deferred Stock Awards Vested, Weighted-Average Grant Date Fair Value (in dollars per share)			$ 18.91
Deferred Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Deferred Stock Awards Granted (in shares)			319,083
Performance Stock Awards and Deferred Stock Awards Vested (in shares)			(256,511)
Deferred Stock Awards Forfeited (in shares)			(17,922)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Deferred Stock Awards Granted, Weighted-Average Grant Date Fair Value (in dollars per share)	$ 0	$ 18.31	$ 19.96	$ 17.59
Performance Stock Awards and Deferred Stock Awards Vested, Weighted-Average Grant Date Fair Value (in dollars per share)			18.58
Deferred Stock Awards Forfeited, Weighted-Average Grant Date Fair Value (in dollars per share)			$ 18.22

Stock Based Compensation (Addit

Stock Based Compensation (Additional Information Regarding Stock Award Activity) (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Deferred Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-Average Grant Date Fair Value of Deferred Stock Granted During the Period (per share)		$ 0	$ 18.31	$ 19.96	$ 17.59
Total Grant Date Fair Value of Deferred Stock Vested During the Period		$ 108	$ 32	$ 4,766	$ 4,109
Performance Share Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Liability Awards Paid During the Period	[1]	$ 0	$ 0	$ 1,127	$ 0
[1]	Amount reflects the issuance of performance share awards related to the 2013-15 Performance Share Plan during the period.

Stock Based Compensation (Outst

Stock Based Compensation (Outstanding Employee Stock Awards) (Details) - $ / shares		May 24, 2016	May 12, 2016	May 01, 2015	May 09, 2014	Jan. 03, 2014	Sep. 30, 2016	Dec. 31, 2015
Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant Date Fair Value (in dollars per share)							$ 19.67	$ 18.67
Unvested Shares							1,066,464	959,446
Deferred Stock Awards [Member] | Deferred Stock Award, Granted January 3, 2014 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Net Shares Granted	[1]					86,512
Grant Date Fair Value (in dollars per share)						$ 16.45
Unvested Shares							52,886
Deferred Stock Awards [Member] | Deferred Stock Award, Granted January 3, 2014 [Member] | Share-based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage						20.00%
Deferred Stock Awards [Member] | Deferred Stock Award, Granted January 3, 2014 [Member] | Share-based Compensation Award, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage						20.00%
Deferred Stock Awards [Member] | Deferred Stock Award, Granted January 3, 2014 [Member] | Share-based Compensation Award, Tranche Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage						20.00%
Deferred Stock Awards [Member] | Deferred Stock Award, Granted January 3, 2014 [Member] | Share-based Compensation Award, Tranche Four [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage						20.00%
Deferred Stock Awards [Member] | Deferred Stock Award, Granted January 3, 2014 [Member] | Share-based Compensation Award, Tranche Five [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage						20.00%
Deferred Stock Awards [Member] | Deferred Stock Award, Granted May 9, 2014 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Net Shares Granted	[1]				145,330
Grant Date Fair Value (in dollars per share)					$ 18.46
Unvested Shares							46,555
Deferred Stock Awards [Member] | Deferred Stock Award, Granted May 9, 2014 [Member] | Share-based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage					25.00%
Deferred Stock Awards [Member] | Deferred Stock Award, Granted May 9, 2014 [Member] | Share-based Compensation Award, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage					25.00%
Deferred Stock Awards [Member] | Deferred Stock Award, Granted May 9, 2014 [Member] | Share-based Compensation Award, Tranche Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage					25.00%
Deferred Stock Awards [Member] | Deferred Stock Award, Granted May 9, 2014 [Member] | Share-based Compensation Award, Tranche Four [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage					25.00%
Deferred Stock Awards [Member] | Deferred Stock Award, Granted May 1, 2015 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Net Shares Granted	[1]			243,884
Grant Date Fair Value (in dollars per share)				$ 17.59
Unvested Shares							138,816
Deferred Stock Awards [Member] | Deferred Stock Award, Granted May 1, 2015 [Member] | Share-based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage				25.00%
Deferred Stock Awards [Member] | Deferred Stock Award, Granted May 1, 2015 [Member] | Share-based Compensation Award, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage				25.00%
Deferred Stock Awards [Member] | Deferred Stock Award, Granted May 1, 2015 [Member] | Share-based Compensation Award, Tranche Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage				25.00%
Deferred Stock Awards [Member] | Deferred Stock Award, Granted May 1, 2015 [Member] | Share-based Compensation Award, Tranche Four [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage				25.00%
Deferred Stock Awards [Member] | Deferred Stock Award, Granted May 12, 2016 [Member] | Board of Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Net Shares Granted	[1]		31,368
Grant Date Fair Value (in dollars per share)			$ 20.40
Unvested Shares							31,368
Deferred Stock Awards [Member] | Deferred Stock Award, Granted May 12, 2016 [Member] | Share-based Compensation Award, Tranche One [Member] | Board of Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			100.00%
Deferred Stock Awards [Member] | Deferred Stock Award, Granted May 24, 2016 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Net Shares Granted	[1]	259,957
Grant Date Fair Value (in dollars per share)		$ 19.91
Unvested Shares							207,412
Deferred Stock Awards [Member] | Deferred Stock Award, Granted May 24, 2016 [Member] | Share-based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage		25.00%
Deferred Stock Awards [Member] | Deferred Stock Award, Granted May 24, 2016 [Member] | Share-based Compensation Award, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage		25.00%
Deferred Stock Awards [Member] | Deferred Stock Award, Granted May 24, 2016 [Member] | Share-based Compensation Award, Tranche Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage		25.00%
Deferred Stock Awards [Member] | Deferred Stock Award, Granted May 24, 2016 [Member] | Share-based Compensation Award, Tranche Four [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage		25.00%
Performance Share Program Award [Member] | Performance Share Program Award, Granted May 9, 2014 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Net Shares Granted	[1]				0
Grant Date Fair Value (in dollars per share)					$ 22
Unvested Shares	[2]						155,919
Performance Share Program Award [Member] | Performance Share Program Award, Granted May 1, 2015 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Net Shares Granted	[1]			0
Grant Date Fair Value (in dollars per share)				$ 18.42
Unvested Shares	[2]						297,424
Performance Share Program Award [Member] | Performance Share Program Award, Granted May 24, 2016 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Net Shares Granted	[1]	0
Grant Date Fair Value (in dollars per share)		$ 23.02
Unvested Shares	[2]						136,084
[1]	Amounts reflect the total grant to employees and independent directors, net of shares surrendered upon vesting to satisfy required minimum tax withholding obligations through September 30, 2016.
[2]	Estimated based on Piedmont's cumulative TSR for the respective performance period through September 30, 2016. Share estimates are subject to change in future periods based on both Piedmont's and its peers' stock performance and dividends paid.

Earnings Per Share (Details)

Earnings Per Share (Details) - shares		3 Months Ended		9 Months Ended
		Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Earnings Per Share [Abstract]
Weighted-average common shares – basic		145,231,160	148,855,336	145,228,755	152,231,060
Deferred and performance stock awards (in shares)		438,000	321,000	372,000	268,000
Weighted-average common shares outstanding – diluted	[1]	145,669,237	149,176,207	145,601,026	152,499,430
Common stock, shares outstanding		145,233,753		145,233,753		145,511,644
[1]	Due to repurchases of common stock during the current year, Piedmont has 145,233,753 shares of common stock outstanding as of September 30, 2016.

Guarantor and Non-Guarantor F53

Guarantor and Non-Guarantor Financial Information - Condensed Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015	Sep. 30, 2015	Dec. 31, 2014
Assets:
Land	$ 663,697	$ 676,091
Buildings and improvements, less accumulated depreciation	2,897,639	2,837,463
Intangible lease assets, less accumulated amortization	92,356	84,663
Construction in progress	35,086	20,975
Real estate assets held for sale, net	0	76,614
Total real estate assets	3,688,778	3,695,806
Investments in and amounts due from unconsolidated joint ventures	7,351	7,577
Cash and cash equivalents	6,032	5,441	$ 7,702	$ 12,306
Tenant and straight-line rent receivables, net	183,596	173,732
Advances to affiliates	0	0
Investment in subsidiary	0	0
Note receivable	0	45,400
Prepaid expenses, restricted cash, escrows, and other assets	33,926	29,951
Goodwill	180,097	180,097
Deferred lease costs, net	288,517	288,041
Other assets held for sale, net	0	8,490
Total assets	4,388,297	4,434,535
Liabilities:
Debt, net	1,994,078	2,029,510
Accounts payable, accrued expenses, and accrued capital expenditures	133,112	128,465
Advances from affiliates	0	0
Deferred income	29,006	27,270
Intangible lease liabilities, net	45,283	42,853
Interest rate swaps	17,835	9,993
Total liabilities	2,219,314	2,238,091
Stockholders’ Equity:
Common stock	1,452	1,455
Additional paid-in capital	3,672,218	3,669,977
Cumulative distributions in excess of earnings	(1,499,374)	(1,477,674)
Other comprehensive income/(loss)	(7,211)	1,661
Piedmont stockholders’ equity	2,167,085	2,195,419
Noncontrolling interest	1,898	1,025
Total stockholders’ equity	2,168,983	2,196,444		2,312,015
Total liabilities and stockholders’ equity	4,388,297	4,434,535
Eliminations [Member]
Assets:
Land	0	0
Buildings and improvements, less accumulated depreciation	(300)	(300)
Intangible lease assets, less accumulated amortization	0	0
Construction in progress	0	0
Real estate assets held for sale, net		0
Total real estate assets	(300)	(300)
Investments in and amounts due from unconsolidated joint ventures	0	0
Cash and cash equivalents	0	0	0	0
Tenant and straight-line rent receivables, net	0	0
Advances to affiliates	(7,634,185)	(7,325,136)
Investment in subsidiary	(3,661,246)	(3,752,709)
Note receivable	(184,700)	(113,240)
Prepaid expenses, restricted cash, escrows, and other assets	(1,703)	(1,258)
Goodwill	0	0
Deferred lease costs, net	0	0
Other assets held for sale, net		0
Total assets	(11,482,134)	(11,192,643)
Liabilities:
Debt, net	(184,700)	(113,240)
Accounts payable, accrued expenses, and accrued capital expenditures	(1,704)	(1,258)
Advances from affiliates	(7,729,252)	(7,402,632)
Deferred income	0	0
Intangible lease liabilities, net	0	0
Interest rate swaps	0	0
Total liabilities	(7,915,656)	(7,517,130)
Stockholders’ Equity:
Common stock	0	0
Additional paid-in capital	(3,661,245)	(3,752,710)
Cumulative distributions in excess of earnings	94,767	77,197
Other comprehensive income/(loss)	0	0
Piedmont stockholders’ equity	(3,566,478)	(3,675,513)
Noncontrolling interest	0	0
Total stockholders’ equity	(3,566,478)	(3,675,513)
Total liabilities and stockholders’ equity	(11,482,134)	(11,192,643)
Issuer [Member]
Assets:
Land	48,213	54,459
Buildings and improvements, less accumulated depreciation	238,912	270,057
Intangible lease assets, less accumulated amortization	861	1,268
Construction in progress	1,136	240
Real estate assets held for sale, net		76,614
Total real estate assets	289,122	402,638
Investments in and amounts due from unconsolidated joint ventures	7,351	7,577
Cash and cash equivalents	3,591	2,174	3,935	8,143
Tenant and straight-line rent receivables, net	20,398	23,738
Advances to affiliates	6,350,066	6,073,606
Investment in subsidiary	0	0
Note receivable	88,910	134,750
Prepaid expenses, restricted cash, escrows, and other assets	12,148	7,091
Goodwill	180,097	180,097
Deferred lease costs, net	17,486	20,939
Other assets held for sale, net		8,490
Total assets	6,969,169	6,861,100
Liabilities:
Debt, net	1,675,263	1,552,007
Accounts payable, accrued expenses, and accrued capital expenditures	18,061	18,954
Advances from affiliates	659,326	580,526
Deferred income	6,741	5,905
Intangible lease liabilities, net	0	0
Interest rate swaps	17,835	9,993
Total liabilities	2,377,226	2,167,385
Stockholders’ Equity:
Common stock	0	0
Additional paid-in capital	3,657,063	3,748,524
Cumulative distributions in excess of earnings	942,091	943,530
Other comprehensive income/(loss)	(7,211)	1,661
Piedmont stockholders’ equity	4,591,943	4,693,715
Noncontrolling interest	0	0
Total stockholders’ equity	4,591,943	4,693,715
Total liabilities and stockholders’ equity	6,969,169	6,861,100
Guarantor [Member]
Assets:
Land	0	0
Buildings and improvements, less accumulated depreciation	0	0
Intangible lease assets, less accumulated amortization	0	0
Construction in progress	0	0
Real estate assets held for sale, net		0
Total real estate assets	0	0
Investments in and amounts due from unconsolidated joint ventures	0	0
Cash and cash equivalents	150	150	151	1,790
Tenant and straight-line rent receivables, net	0	0
Advances to affiliates	1,284,119	1,251,530
Investment in subsidiary	3,661,064	3,752,523
Note receivable	0	0
Prepaid expenses, restricted cash, escrows, and other assets	37	0
Goodwill	0	0
Deferred lease costs, net	0	0
Other assets held for sale, net		0
Total assets	4,945,370	5,004,203
Liabilities:
Debt, net	0	0
Accounts payable, accrued expenses, and accrued capital expenditures	644	580
Advances from affiliates	5,071,498	5,033,266
Deferred income	0	0
Intangible lease liabilities, net	0	0
Interest rate swaps	0	0
Total liabilities	5,072,142	5,033,846
Stockholders’ Equity:
Common stock	1,452	1,455
Additional paid-in capital	3,675,090	3,672,849
Cumulative distributions in excess of earnings	(3,803,314)	(3,703,947)
Other comprehensive income/(loss)	0	0
Piedmont stockholders’ equity	(126,772)	(29,643)
Noncontrolling interest	0	0
Total stockholders’ equity	(126,772)	(29,643)
Total liabilities and stockholders’ equity	4,945,370	5,004,203
Non-Guarantor Subsidiaries [Member]
Assets:
Land	615,484	621,632
Buildings and improvements, less accumulated depreciation	2,659,027	2,567,706
Intangible lease assets, less accumulated amortization	91,495	83,395
Construction in progress	33,950	20,735
Real estate assets held for sale, net		0
Total real estate assets	3,399,956	3,293,468
Investments in and amounts due from unconsolidated joint ventures	0	0
Cash and cash equivalents	2,291	3,117	$ 3,616	$ 2,373
Tenant and straight-line rent receivables, net	163,198	149,994
Advances to affiliates	0	0
Investment in subsidiary	182	186
Note receivable	95,790	23,890
Prepaid expenses, restricted cash, escrows, and other assets	23,444	24,118
Goodwill	0	0
Deferred lease costs, net	271,031	267,102
Other assets held for sale, net		0
Total assets	3,955,892	3,761,875
Liabilities:
Debt, net	503,515	590,743
Accounts payable, accrued expenses, and accrued capital expenditures	116,111	110,189
Advances from affiliates	1,998,428	1,788,840
Deferred income	22,265	21,365
Intangible lease liabilities, net	45,283	42,853
Interest rate swaps	0	0
Total liabilities	2,685,602	2,553,990
Stockholders’ Equity:
Common stock	0	0
Additional paid-in capital	1,310	1,314
Cumulative distributions in excess of earnings	1,267,082	1,205,546
Other comprehensive income/(loss)	0	0
Piedmont stockholders’ equity	1,268,392	1,206,860
Noncontrolling interest	1,898	1,025
Total stockholders’ equity	1,270,290	1,207,885
Total liabilities and stockholders’ equity	$ 3,955,892	$ 3,761,875

Guarantor and Non-Guarantor F54

Guarantor and Non-Guarantor Financial Information - Condensed Consolidated Statements of Income (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended		12 Months Ended
		Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Revenues:
Rental income		$ 113,821	$ 117,994	$ 340,326	$ 353,255
Tenant reimbursements		24,163	30,273	70,000	90,476
Property management fee revenue		501	548	1,478	1,577
Total revenues		138,485	148,815	411,804	445,308
Expenses:
Property operating costs		54,867	61,653	161,438	187,368
Depreciation		31,610	31,199	94,948	103,470
Amortization		18,640	14,021	53,848	43,646
Impairment loss on real estate assets	[1]	22,590	34,815	30,898	40,169
General and administrative		7,429	8,260	23,518	22,750
Operating expenses		135,136	149,948	364,650	397,403
Real estate operating income/(loss)		3,349	(1,133)	47,154	47,905
Other income (expense):
Interest expense		(15,496)	(18,832)	(48,294)	(56,020)
Other income/(expense)		(720)	803	(467)	1,218
Recovery from casualty event		34	0	34	0
Equity in income of unconsolidated joint ventures		128	135	354	418
Other income (expense)		(16,054)	(17,894)	(48,373)	(54,384)
Loss from continuing operations		(12,705)	(19,027)	(1,219)	(6,479)
Discontinued operations:
Operating income		1	16	0	13
Loss on sale of real estate assets		0	(2)	0	(2)
Income from discontinued operations		1	14	0	11
Gain/(loss) on sale of real estate assets		(57)	17,142	78,910	53,826
Net income/(loss)		(12,761)	(1,871)	77,691	47,358
Less: Net loss/(income) applicable to noncontrolling interest		15	(4)	7	(12)	$ (15)
Net income/(loss) applicable to Piedmont		(12,746)	(1,875)	77,698	47,346	$ 172,990
Eliminations [Member]
Revenues:
Rental income		(464)	(735)	(1,983)	(2,172)
Tenant reimbursements		(237)	(31)	(405)	(329)
Property management fee revenue		(3,484)	(4,055)	(11,002)	(11,966)
Total revenues		(4,185)	(4,821)	(13,390)	(14,467)
Expenses:
Property operating costs		(4,240)	(5,031)	(13,514)	(15,068)
Depreciation		0	0	0	0
Amortization		0	0	0	0
Impairment loss on real estate assets		0	0	0	0
General and administrative		(8,857)	(9,435)	(28,416)	(26,231)
Operating expenses		(13,097)	(14,466)	(41,930)	(41,299)
Real estate operating income/(loss)		8,912	9,645	28,540	26,832
Other income (expense):
Interest expense		3,252	2,544	8,219	8,702
Other income/(expense)		(3,252)	(2,544)	(8,219)	(8,702)
Recovery from casualty event		0		0
Equity in income of unconsolidated joint ventures		0	0	0	0
Other income (expense)		0	0	0	0
Loss from continuing operations		8,912	9,645	28,540	26,832
Discontinued operations:
Operating income		0	0		0
Loss on sale of real estate assets			0		0
Income from discontinued operations		0	0		0
Gain/(loss) on sale of real estate assets		0	0	0	0
Net income/(loss)		8,912	9,645	28,540	26,832
Less: Net loss/(income) applicable to noncontrolling interest		0	0	0	0
Net income/(loss) applicable to Piedmont		8,912	9,645	28,540	26,832
Issuer [Member]
Revenues:
Rental income		12,862	15,841	42,990	51,824
Tenant reimbursements		3,430	3,369	10,455	11,171
Property management fee revenue		0	0	0	0
Total revenues		16,292	19,210	53,445	62,995
Expenses:
Property operating costs		7,820	9,238	24,583	29,459
Depreciation		3,617	4,943	12,993	15,904
Amortization		863	1,126	2,854	3,477
Impairment loss on real estate assets		0	0	5,972	5,354
General and administrative		7,187	8,118	22,802	22,211
Operating expenses		19,487	23,425	69,204	76,405
Real estate operating income/(loss)		(3,195)	(4,215)	(15,759)	(13,410)
Other income (expense):
Interest expense		(11,799)	(12,963)	(36,159)	(39,592)
Other income/(expense)		2,608	3,199	7,008	9,357
Recovery from casualty event		0		0
Equity in income of unconsolidated joint ventures		128	135	354	418
Other income (expense)		(9,063)	(9,629)	(28,797)	(29,817)
Loss from continuing operations		(12,258)	(13,844)	(44,556)	(43,227)
Discontinued operations:
Operating income		0	16		13
Loss on sale of real estate assets			(2)		(2)
Income from discontinued operations		0	14		11
Gain/(loss) on sale of real estate assets		134	17,142	32,146	53,826
Net income/(loss)		(12,124)	3,312	(12,410)	10,610
Less: Net loss/(income) applicable to noncontrolling interest		0	0	0	0
Net income/(loss) applicable to Piedmont		(12,124)	3,312	(12,410)	10,610
Guarantor [Member]
Revenues:
Rental income		0	0	0	0
Tenant reimbursements		0	0	0	0
Property management fee revenue		0	0	0	0
Total revenues		0	0	0	0
Expenses:
Property operating costs		0	0	0	0
Depreciation		0	0	0	0
Amortization		0	0	0	0
Impairment loss on real estate assets		0	0	0	0
General and administrative		83	71	251	266
Operating expenses		83	71	251	266
Real estate operating income/(loss)		(83)	(71)	(251)	(266)
Other income (expense):
Interest expense		0	0	0	0
Other income/(expense)		0	0	282	0
Recovery from casualty event		0		0
Equity in income of unconsolidated joint ventures		0	0	0	0
Other income (expense)		0	0	282	0
Loss from continuing operations		(83)	(71)	31	(266)
Discontinued operations:
Operating income		0	0		0
Loss on sale of real estate assets			0		0
Income from discontinued operations		0	0		0
Gain/(loss) on sale of real estate assets		0	0	0	0
Net income/(loss)		(83)	(71)	31	(266)
Less: Net loss/(income) applicable to noncontrolling interest		0	0	0	0
Net income/(loss) applicable to Piedmont		(83)	(71)	31	(266)
Non-Guarantor Subsidiaries [Member]
Revenues:
Rental income		101,423	102,888	299,319	303,603
Tenant reimbursements		20,970	26,935	59,950	79,634
Property management fee revenue		3,985	4,603	12,480	13,543
Total revenues		126,378	134,426	371,749	396,780
Expenses:
Property operating costs		51,287	57,446	150,369	172,977
Depreciation		27,993	26,256	81,955	87,566
Amortization		17,777	12,895	50,994	40,169
Impairment loss on real estate assets		22,590	34,815	24,926	34,815
General and administrative		9,016	9,506	28,881	26,504
Operating expenses		128,663	140,918	337,125	362,031
Real estate operating income/(loss)		(2,285)	(6,492)	34,624	34,749
Other income (expense):
Interest expense		(6,949)	(8,413)	(20,354)	(25,130)
Other income/(expense)		(76)	148	462	563
Recovery from casualty event		34		34
Equity in income of unconsolidated joint ventures		0	0	0	0
Other income (expense)		(6,991)	(8,265)	(19,858)	(24,567)
Loss from continuing operations		(9,276)	(14,757)	14,766	10,182
Discontinued operations:
Operating income		1	0		0
Loss on sale of real estate assets			0		0
Income from discontinued operations		1	0		0
Gain/(loss) on sale of real estate assets		(191)	0	46,764	0
Net income/(loss)		(9,466)	(14,757)	61,530	10,182
Less: Net loss/(income) applicable to noncontrolling interest		15	(4)	7	(12)
Net income/(loss) applicable to Piedmont		$ (9,451)	$ (14,761)	$ 61,537	$ 10,170
[1]	The fair value measurements used in the evaluation of the non-financial assets above are considered to be Level 1 valuations within the fair value hierarchy as defined by GAAP, as there are direct observations and transactions involving the assets by unrelated, third-party purchasers.

Guarantor and Non-Guarantor F55

Guarantor and Non-Guarantor Financial Information - Condensed Consolidated Statements of Cash Flows (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Condensed Financial Statements, Captions [Line Items]
Net Cash Provided by Operating Activities	$ 172,036	$ 134,261
Cash Flows from Investing Activities:
Investment in real estate assets, consolidated joint venture, and real estate related intangibles, net of accruals	(321,139)	(157,893)
Intercompany note receivable	0	0
Redemption of noncontrolling interest in unconsolidated variable interest entity	0	(4,000)
Net sales proceeds from wholly-owned properties	304,902	151,564
Deferred lease costs paid	(15,345)	(23,889)
Net cash used in investing activities	(31,582)	(34,218)
Cash Flows from Financing Activities:
Debt issuance costs paid	(212)	(1,048)
Proceeds from debt	552,000	1,205,857
Repayments of debt	(589,532)	(1,055,902)
Intercompany note payable	0
Costs of issuance of common stock	(239)	(326)
Shares withheld to pay tax obligations related to employee stock compensation	(2,328)	(1,665)
Repurchases of common stock as part of announced plan	(7,943)	(155,653)
(Distributions to)/repayments from affiliates	0	0
Dividends paid and discount on dividend reinvestments	(91,609)	(95,910)
Net cash used in financing activities	(139,863)	(104,647)
Net increase/(decrease) in cash and cash equivalents	591	(4,604)
Cash and cash equivalents, beginning of period	5,441	12,306
Cash and cash equivalents, end of period	6,032	7,702
Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Net Cash Provided by Operating Activities	28,540	26,833
Cash Flows from Investing Activities:
Investment in real estate assets, consolidated joint venture, and real estate related intangibles, net of accruals	0	0
Intercompany note receivable	71,460	(72,000)
Redemption of noncontrolling interest in unconsolidated variable interest entity		0
Net sales proceeds from wholly-owned properties	0	0
Deferred lease costs paid	0	0
Net cash used in investing activities	71,460	(72,000)
Cash Flows from Financing Activities:
Debt issuance costs paid	0	0
Proceeds from debt	0	0
Repayments of debt	0	72,000
Intercompany note payable	(71,460)
Costs of issuance of common stock	0	0
Shares withheld to pay tax obligations related to employee stock compensation	0	0
Repurchases of common stock as part of announced plan	0	0
(Distributions to)/repayments from affiliates	(28,540)	(26,833)
Dividends paid and discount on dividend reinvestments	0	0
Net cash used in financing activities	(100,000)	45,167
Net increase/(decrease) in cash and cash equivalents	0	0
Cash and cash equivalents, beginning of period	0	0
Cash and cash equivalents, end of period	0	0
Issuer [Member]
Condensed Financial Statements, Captions [Line Items]
Net Cash Provided by Operating Activities	(18,977)	(41,584)
Cash Flows from Investing Activities:
Investment in real estate assets, consolidated joint venture, and real estate related intangibles, net of accruals	(24,255)	(28,249)
Intercompany note receivable	440	72,000
Redemption of noncontrolling interest in unconsolidated variable interest entity		0
Net sales proceeds from wholly-owned properties	187,192	151,564
Deferred lease costs paid	(2,021)	(2,577)
Net cash used in investing activities	161,356	192,738
Cash Flows from Financing Activities:
Debt issuance costs paid	(212)	(545)
Proceeds from debt	552,000	1,046,578
Repayments of debt	(421,000)	(950,000)
Intercompany note payable	(9,600)
Costs of issuance of common stock	0	0
Shares withheld to pay tax obligations related to employee stock compensation	0	0
Repurchases of common stock as part of announced plan	0	0
(Distributions to)/repayments from affiliates	(262,150)	(251,395)
Dividends paid and discount on dividend reinvestments	0	0
Net cash used in financing activities	(140,962)	(155,362)
Net increase/(decrease) in cash and cash equivalents	1,417	(4,208)
Cash and cash equivalents, beginning of period	2,174	8,143
Cash and cash equivalents, end of period	3,591	3,935
Guarantor [Member]
Condensed Financial Statements, Captions [Line Items]
Net Cash Provided by Operating Activities	4,121	3,772
Cash Flows from Investing Activities:
Investment in real estate assets, consolidated joint venture, and real estate related intangibles, net of accruals	0	0
Intercompany note receivable	0	0
Redemption of noncontrolling interest in unconsolidated variable interest entity		0
Net sales proceeds from wholly-owned properties	0	0
Deferred lease costs paid	0	0
Net cash used in investing activities	0	0
Cash Flows from Financing Activities:
Debt issuance costs paid	0	0
Proceeds from debt	0	0
Repayments of debt	0	0
Intercompany note payable	0
Costs of issuance of common stock	(239)	(326)
Shares withheld to pay tax obligations related to employee stock compensation	(2,328)	(1,665)
Repurchases of common stock as part of announced plan	(7,943)	(155,653)
(Distributions to)/repayments from affiliates	97,990	248,135
Dividends paid and discount on dividend reinvestments	(91,601)	(95,902)
Net cash used in financing activities	(4,121)	(5,411)
Net increase/(decrease) in cash and cash equivalents	0	(1,639)
Cash and cash equivalents, beginning of period	150	1,790
Cash and cash equivalents, end of period	150	151
Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Net Cash Provided by Operating Activities	158,352	145,240
Cash Flows from Investing Activities:
Investment in real estate assets, consolidated joint venture, and real estate related intangibles, net of accruals	(296,884)	(129,644)
Intercompany note receivable	(71,900)	0
Redemption of noncontrolling interest in unconsolidated variable interest entity		(4,000)
Net sales proceeds from wholly-owned properties	117,710	0
Deferred lease costs paid	(13,324)	(21,312)
Net cash used in investing activities	(264,398)	(154,956)
Cash Flows from Financing Activities:
Debt issuance costs paid	0	(503)
Proceeds from debt	0	159,279
Repayments of debt	(168,532)	(177,902)
Intercompany note payable	81,060
Costs of issuance of common stock	0	0
Shares withheld to pay tax obligations related to employee stock compensation	0	0
Repurchases of common stock as part of announced plan	0	0
(Distributions to)/repayments from affiliates	192,700	30,093
Dividends paid and discount on dividend reinvestments	(8)	(8)
Net cash used in financing activities	105,220	10,959
Net increase/(decrease) in cash and cash equivalents	(826)	1,243
Cash and cash equivalents, beginning of period	3,117	2,373
Cash and cash equivalents, end of period	$ 2,291	$ 3,616

Subsequent Events (Details)

Subsequent Events (Details) - Subsequent Event [Member] - USD ($) $ / shares in Units, $ in Millions	Nov. 01, 2016	Oct. 07, 2016
Subsequent Event [Line Items]
Dividends declared (in dollars per share)	$ 0.21
Galleria 200 building [Member]
Subsequent Event [Line Items]
Acquisition price		$ 69.6