Variable Interest Entities (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Variable Interest Entity [Line Items]
Payment to settle redemption option	$ 4,000	$ 0
Medici Atlanta LLC [Member]
Variable Interest Entity [Line Items]
Payment to settle redemption option	$ 4,000
Eye Street 1201 NW Associates LLC [Member]
Variable Interest Entity [Line Items]
Piedmont’s % Ownership of Entity	49.50%
Net Carrying Amount	$ (3,400)		$ (2,800)
Variable interest entity, cash flow percent entitled to entity	100.00%
Eye Street 1225 NW Associates LLC [Member]
Variable Interest Entity [Line Items]
Piedmont’s % Ownership of Entity	49.50%
Net Carrying Amount	$ 1,100		(1,100)
Variable interest entity, cash flow percent entitled to entity	100.00%
Piedmont 500 W. Monroe Fee LLC [Member]
Variable Interest Entity [Line Items]
Piedmont’s % Ownership of Entity	100.00%
Net Carrying Amount	$ 243,600		245,300
Land Parcel Adjacent to 400 Town Park Building [Member]
Variable Interest Entity [Line Items]
Piedmont’s % Ownership of Entity	100.00%
Net Carrying Amount	$ 8,000		$ 7,900