Consolidated Statements of Stockholders' Equity (USD $) In Thousands, except Share data, unless otherwise specified	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Cumulative Distributions in Excess of Earnings [Member]	Other Comprehensive Loss [Member]	Non-controlling Interest [Member]
Balance at Dec. 31, 2012	$ 2,640,495	$ 1,676	$ 3,667,051	$ (1,022,681)	$ (7,160)	$ 1,609
Balance (in shares) at Dec. 31, 2012		167,556,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share repurchases as part of an announced plan	(175,269)	(102)		(175,167)
Share repurchases as part of an announced plan, shares		(10,246,000)
Offering costs associated with the issuance of common stock	(91)		(91)
Dividends to common stockholders ($0.80 (YTD 2013) and $0.40 (YTD 2014) per share), distributions to noncontrolling interest, and dividends reinvested	(132,301)		(197)	(132,089)		(15)
Shares issued and amortized under the 2007 Omnibus Incentive Plan, net of tax	2,144	1	2,143
Shares issued and amortized under the 2007 Omnibus Incentive Plan, net of tax (in shares)		151,000
Net income attributable to noncontrolling interest	15					15
Net income attributable to Piedmont	98,728			98,728
Other comprehensive income (loss)	27,438				27,438
Balance at Dec. 31, 2013	2,461,159	1,575	3,668,906	(1,231,209)	20,278	1,609
Balance (in shares) at Dec. 31, 2013	157,460,903	157,461,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share repurchases as part of an announced plan	(52,680)	(32)		(52,648)
Share repurchases as part of an announced plan, shares		(3,183,000)
Retirement of shares returned from escrow	(1,479)	(1)	(1,478)
Retirement of shares returned from escrow, shares		(85,000)
Dividends to common stockholders ($0.80 (YTD 2013) and $0.40 (YTD 2014) per share), distributions to noncontrolling interest, and dividends reinvested	(61,827)		(97)	(61,722)		(8)
Shares issued and amortized under the 2007 Omnibus Incentive Plan, net of tax	1,506	1	1,505
Shares issued and amortized under the 2007 Omnibus Incentive Plan, net of tax (in shares)		131,000
Net income attributable to noncontrolling interest	8					8
Net income attributable to Piedmont	21,672			21,672
Other comprehensive income (loss)	(11,174)				(11,174)
Balance at Jun. 30, 2014	$ 2,357,185	$ 1,543	$ 3,668,836	$ (1,323,907)	$ 9,104	$ 1,609
Balance (in shares) at Jun. 30, 2014	154,324,076	154,324,000