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Properties, net (Details 3) (USD $)
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12 Months Ended | 0 Months Ended | 12 Months Ended | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
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Dec. 31, 2013
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Dec. 31, 2012
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Dec. 31, 2011
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Dec. 31, 2013
Non-operating Properties
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Dec. 31, 2012
Non-operating Properties
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Dec. 23, 2013
Secured Debt
December 2013 Portfolio Conveyance
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Jul. 02, 2012
Secured Debt
400 Professional Drive
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Dec. 23, 2013
Secured Debt
Fair value measurement on a nonrecurring basis
December 2013 Portfolio Conveyance
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Jul. 02, 2012
Secured Debt
Fair value measurement on a nonrecurring basis
400 Professional Drive
|
Dec. 31, 2013
Operating properties
buillding
sqft
|
Dec. 31, 2012
Operating properties
buillding
sqft
|
Dec. 31, 2013
Operating properties
920 Elkridge Landing Road
buillding
sqft
|
Dec. 31, 2013
Operating properties
4230 Forbes Boulevard
buillding
sqft
|
Dec. 31, 2013
Operating properties
December 2013 Colorado Springs Portfolio Disposition
buillding
sqft
|
Dec. 31, 2013
Operating properties
December 2013 Portfolio Conveyance
buillding
sqft
|
Dec. 31, 2012
Operating properties
White Marsh Portfolio
buillding
sqft
|
Dec. 31, 2012
Operating properties
1101 Sentry Gateway
buillding
sqft
|
Dec. 31, 2012
Operating properties
222 and 224 Schilling Circle
buillding
sqft
|
Dec. 31, 2012
Operating properties
15 and 45 West Gude Drive
buillding
sqft
|
Dec. 31, 2012
Operating properties
11800 Tech Road
buillding
sqft
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Dec. 31, 2012
Operating properties
400 Professional Drive
buillding
sqft
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Dec. 31, 2012
Operating properties
July 2012 Portfolio Disposition
buillding
sqft
|
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| Dispositions | ||||||||||||||||||||||
| Number of Buildings Disposed | 31 | 35 | 1 | 1 | 15 | 14 | 5 | 1 | 2 | 2 | 1 | 1 | 23 | |||||||||
| Total Rentable Square Feet | 2,345,000 | 2,302,000 | 103,000 | 56,000 | 1,165,000 | 1,021,000 | 163,000 | 95,000 | 56,000 | 231,000 | 240,000 | 130,000 | 1,387,000 | |||||||||
| Transaction Value of Operating Property Dispositions | $ 293,301,000 | $ 285,506,000 | $ 6,900,000 | $ 5,600,000 | $ 133,925,000 | $ 146,876,000 | $ 19,100,000 | $ 13,500,000 | $ 4,400,000 | $ 49,107,000 | $ 21,300,000 | $ 16,198,000 | $ 161,901,000 | |||||||||
| Gain on Sale | 2,671,000 | 21,186,000 | 0 | 1,507,000 | 1,164,000 | 0 | 2,445,000 | 1,739,000 | 102,000 | 0 | 0 | 0 | 16,900,000 | |||||||||
| Sale Price of Non-operating Properties | 3,500,000 | 28,100,000 | ||||||||||||||||||||
| Debt settled through the surrender of real estate assets | 146,500,000 | 15,000,000 | ||||||||||||||||||||
| Fair value of real estate disposed in settlement of debt | 74,000,000 | 11,000,000 | ||||||||||||||||||||
| Gain on early extinguishment of debt | $ (27,030,000) | $ (943,000) | $ (1,639,000) | $ 67,800,000 | $ 3,700,000 | |||||||||||||||||