Investment in Office Properties, Dispositions (Details) (USD $)	12 Months Ended
	Dec. 31, 2012 sqft		Dec. 31, 2011 sqft		Dec. 31, 2010 sqft
Summary of Dispositions [Abstract]
Square Feet (in square feet)	3,978,000		3,711,000		163,000
Parkway's share of Gross Sales Price of assets under agreement to sell	$ 97,400,000
Repayment of mortgage loan on real estate	24,623,000		106,567,000		140,499,000
Non-cash gain on mortgage loan payable-discontinued operations	0		(8,601,000)		0
Gain on sale of real estate from discontinued operations	12,939,000		17,825,000		8,518,000
Non-cash impairment loss on real estate	9,200,000		6,420,000		0
Impairment loss on real estate discontinued operations	0		189,940,000		4,120,000
Long Lived Assets Held-for-sale [Line Items]
Impairment loss on real estate	9,200,000		6,420,000		0
233 North Michigan [Member]
Summary of Dispositions [Abstract]
Square Feet (in square feet)			1,070,000
Gain on sale of real estate from discontinued operations			4,292,000
Greenbrier I & II [Member]
Summary of Dispositions [Abstract]
Square Feet (in square feet)			172,000
Gain on sale of real estate from discontinued operations			1,205,000
Glen Forest [Member]
Summary of Dispositions [Abstract]
Square Feet (in square feet)			81,000
Gain on sale of real estate from discontinued operations			1,070,000
Sugar Grove [Member]
Summary of Dispositions [Abstract]
Square Feet (in square feet)	124,000
Gain on sale of real estate from discontinued operations	3,246,000
Tower at Gervais [Member]
Summary of Dispositions [Abstract]
Square Feet (in square feet)			298,000	[1]
Gain on sale of real estate from discontinued operations			0	[1]
Non-cash impairment loss on real estate			2,700,000		3,400,000
Long Lived Assets Held-for-sale [Line Items]
Impairment loss on real estate			2,700,000		3,400,000
Wells Fargo [Member]
Summary of Dispositions [Abstract]
Square Feet (in square feet)			134,000
Gain on sale of real estate from discontinued operations			0
Fund I Assets [Member]
Summary of Dispositions [Abstract]
Square Feet (in square feet)			1,956,000
Net proceeds from the sale	14,200,000
Gain on sale of real estate from discontinued operations			11,258,000
Number of real estate properties sold	13		9
Number of assets under agreement that have completed sale	4		9
Area of property under agreement to sell (in millions of square feet)	2,700,000
Gross sales price of assets under agreement to sell	344,300,000
Mortgage loans assumed by buyer for property sold	292,000,000
Proportionate share of mortgage loans assumed	82,400,000
Number of non-core assets sold	4
Falls Pointe [Member]
Summary of Dispositions [Abstract]
Square Feet (in square feet)	107,000
Gain on sale of real estate from discontinued operations	1,357,000
Wink Building [Member]
Summary of Dispositions [Abstract]
Square Feet (in square feet)	32,000
Gain on sale of real estate from discontinued operations	(98,000)
111 East Wacker [Member]
Summary of Dispositions [Abstract]
Square Feet (in square feet)	1,013,000
Gain on sale of real estate from discontinued operations	3,000
Mortgage loans assumed by buyer for property sold	147,900,000
Non-Core Assets [Member]
Summary of Dispositions [Abstract]
Square Feet (in square feet)	1,932,000	[2]
Gross sales price	147,700,000
Net proceeds from the sale	94,300,000
Gain on sale of real estate from discontinued operations	3,329,000	[2]
Number of real estate properties sold	15
Non-cash impairment loss on real estate			51,200,000		640,000
Mortgage loans assumed by buyer for property sold	41,700,000
Proportionate share of mortgage loans assumed	31,900,000
Number of non-core assets sold	15
Long Lived Assets Held-for-sale [Line Items]
Impairment loss on real estate			51,200,000		640,000
Non-Core Assets [Member] | Jackson, MS [Member]
Summary of Dispositions [Abstract]
Number of real estate properties sold	6
Number of non-core assets sold	6
Non-Core Assets [Member] | Memphis, TN [Member]
Summary of Dispositions [Abstract]
Number of real estate properties sold	4
Number of non-core assets sold	4
Non-Core Assets [Member] | Richmond, VA [Member]
Summary of Dispositions [Abstract]
Number of real estate properties sold	5
Number of non-core assets sold	5
Additional Assets Sold [Member]
Summary of Dispositions [Abstract]
Gross sales price	168,800,000
Net proceeds from the sale	14,800,000
Number of real estate properties sold	4
Renaissance Center [Member]
Summary of Dispositions [Abstract]
Square Feet (in square feet)	189,000
Gain on sale of real estate from discontinued operations	$ 3,032,000

[1] (1)During 2010 and 2011, the Company recognized non-cash impairment losses on this property of $3.4 million and $2.7 million, respectively.

[2] (2)During 2010 and 2011, the Company recognized non-cash impairment losses associated with these properties of $640,000 and $51.2 million, respectively.