Guarantor Financials Guarantor and Non-Guarantor Financial Information - Condensed Consolidated Statements of Income (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Revenues:
Rental income									$ 447,687	$ 415,972	$ 409,711
Tenant reimbursements									104,567	106,754	113,813
Property management fee revenue									2,251	2,318	1,584
Total revenues	142,868	144,631	133,713	133,293	132,379	132,149	130,556	129,960	554,505	525,044	525,108
Expenses:
Property operating costs									222,979	208,280	202,531
Depreciation									122,562	110,359	100,686
Amortization									45,651	49,562	54,008
Impairment loss									1,242	0	0
General and administrative									21,883	20,765	25,072
Operating Expenses									414,317	388,966	382,297
Real estate operating income	33,981	35,563	32,863	37,781	33,846	33,263	34,991	33,978	140,188	136,078	142,811
Other income (expense):
Interest expense									(73,583)	(65,023)	(65,817)
Interest income and other income/(expense)									(2,352)	833	2,866
Litigation settlement recovery/(expense)									1,250	(7,500)	0
Net casualty recoveries/(loss)									10,561	(5,170)	0
Equity in income/(loss) of unconsolidated joint ventures									(3,676)	923	1,619
Loss on consolidation									(898)	0	1,532
Gain on extinguishment of debt									0	0	1,039
Nonoperating Income (Expense)									(68,698)	(75,937)	(58,761)
Income from continuing operations	14,158	18,688	18,279	20,365	12,633	10,222	19,579	17,707	71,490	60,141	84,050
Discontinued operations:
Operating income, excluding impairment loss									2,363	5,501	18,349
Impairment loss									(6,402)	0	0
Gain on sale of real estate assets									31,292	27,577	122,657
Income from discontinued operations	15,468	412	17,083	(5,710)	1,809	612	11,133	19,524	27,253	33,078	141,006
Net income									98,743	93,219	225,056
Less: Net income attributable to noncontrolling interest									(15)	(15)	(15)
Net income attributable to Piedmont	29,623	19,096	35,358	14,651	14,438	10,830	30,708	37,228	98,728	93,204	225,041
Issuer [Member]
Revenues:
Rental income									77,200	72,072	67,669
Tenant reimbursements									16,526	17,100	18,539
Property management fee revenue									0	0	0
Total revenues									93,726	89,172	86,208
Expenses:
Property operating costs									41,833	36,486	40,311
Depreciation									23,857	23,456	21,148
Amortization									5,297	5,524	4,860
Impairment loss									1,242
General and administrative									21,011	19,804	25,029
Operating Expenses									93,240	85,270	91,348
Real estate operating income									486	3,902	(5,140)
Other income (expense):
Interest expense									(22,242)	(12,530)	(8,991)
Interest income and other income/(expense)									10,630	12,226	11,975
Litigation settlement recovery/(expense)									1,250	(7,500)
Net casualty recoveries/(loss)									(567)	(5,195)
Equity in income/(loss) of unconsolidated joint ventures									(3,676)	923	1,619
Loss on consolidation									(898)		0
Gain on extinguishment of debt											0
Nonoperating Income (Expense)									(15,503)	(12,076)	4,603
Income from continuing operations									(15,017)	(8,174)	(537)
Discontinued operations:
Operating income, excluding impairment loss									1,755	5,220	6,842
Impairment loss									(6,402)
Gain on sale of real estate assets									15,046	27,577	12,152
Income from discontinued operations									10,399	32,797	18,994
Net income									(4,618)	24,623	18,457
Less: Net income attributable to noncontrolling interest									0	0	0
Net income attributable to Piedmont									(4,618)	24,623	18,457
Guarantor [Member]
Revenues:
Rental income									0	0	0
Tenant reimbursements									0	0	0
Property management fee revenue									0	0	0
Total revenues									0	0	0
Expenses:
Property operating costs									0	0	0
Depreciation									0	0	0
Amortization									0	0	0
Impairment loss									0
General and administrative									337	294	(50)
Operating Expenses									337	294	(50)
Real estate operating income									(337)	(294)	50
Other income (expense):
Interest expense									0	0	0
Interest income and other income/(expense)									164	15	0
Litigation settlement recovery/(expense)									0	0
Net casualty recoveries/(loss)									0	0
Equity in income/(loss) of unconsolidated joint ventures									0	0	0
Loss on consolidation									0		0
Gain on extinguishment of debt											0
Nonoperating Income (Expense)									164	15	0
Income from continuing operations									(173)	(279)	50
Discontinued operations:
Operating income, excluding impairment loss									0	0	0
Impairment loss									0
Gain on sale of real estate assets									0	0	0
Income from discontinued operations									0	0	0
Net income									(173)	(279)	50
Less: Net income attributable to noncontrolling interest									0	0	0
Net income attributable to Piedmont									(173)	(279)	50
Non-Guarantor Subsidiaries [Member]
Revenues:
Rental income									375,769	348,713	343,492
Tenant reimbursements									88,461	89,937	95,313
Property management fee revenue									15,360	14,350	14,474
Total revenues									479,590	453,000	453,279
Expenses:
Property operating costs									200,472	189,665	177,566
Depreciation									98,705	86,903	79,538
Amortization									40,354	44,038	49,148
Impairment loss									0
General and administrative									24,927	23,574	24,570
Operating Expenses									364,458	344,180	330,822
Real estate operating income									115,132	108,820	122,457
Other income (expense):
Interest expense									(63,900)	(65,001)	(70,526)
Interest income and other income/(expense)									(587)	1,100	4,591
Litigation settlement recovery/(expense)									0	0
Net casualty recoveries/(loss)									11,128	25
Equity in income/(loss) of unconsolidated joint ventures									0	0	0
Loss on consolidation									0		1,532
Gain on extinguishment of debt											1,039
Nonoperating Income (Expense)									(53,359)	(63,876)	(63,364)
Income from continuing operations									61,773	44,944	59,093
Discontinued operations:
Operating income, excluding impairment loss									608	281	11,507
Impairment loss									0
Gain on sale of real estate assets									16,246	0	110,505
Income from discontinued operations									16,854	281	122,012
Net income									78,627	45,225	181,105
Less: Net income attributable to noncontrolling interest									(15)	(15)	(15)
Net income attributable to Piedmont									78,612	45,210	181,090
Eliminations [Member]
Revenues:
Rental income									(5,282)	(4,813)	(1,450)
Tenant reimbursements									(420)	(283)	(39)
Property management fee revenue									(13,109)	(12,032)	(12,890)
Total revenues									(18,811)	(17,128)	(14,379)
Expenses:
Property operating costs									(19,326)	(17,871)	(15,346)
Depreciation									0	0	0
Amortization									0	0	0
Impairment loss									0
General and administrative									(24,392)	(22,907)	(24,477)
Operating Expenses									(43,718)	(40,778)	(39,823)
Real estate operating income									24,907	23,650	25,444
Other income (expense):
Interest expense									12,559	12,508	13,700
Interest income and other income/(expense)									(12,559)	(12,508)	(13,700)
Litigation settlement recovery/(expense)									0	0
Net casualty recoveries/(loss)									0	0
Equity in income/(loss) of unconsolidated joint ventures									0	0	0
Loss on consolidation									0		0
Gain on extinguishment of debt											0
Nonoperating Income (Expense)									0	0	0
Income from continuing operations									24,907	23,650	25,444
Discontinued operations:
Operating income, excluding impairment loss									0	0	0
Impairment loss									0
Gain on sale of real estate assets									0	0	0
Income from discontinued operations									0	0	0
Net income									24,907	23,650	25,444
Less: Net income attributable to noncontrolling interest									0	0	0
Net income attributable to Piedmont									$ 24,907	$ 23,650	$ 25,444