This element represents the amount of gain (loss) on sale of properties during the reporting period net of the applicable income taxes realized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 974
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-15.(a)(1)(ii))
-URI http://asc.fasb.org/extlink&oid=6875705&loc=d3e641549-123027

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- References

No definition available.

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- Definition

Amount charged against operating income increasing loss contingency liability, after adjustments to reduce previously estimated charges.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

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- Definition

The cash inflow from the sale of formerly productive land held for sale, anything permanently fixed to it, including buildings, structures on it, and so forth.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3179-108585

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Dispositions of Properties (Details) - USD ($) $ in Thousands				3 Months Ended		6 Months Ended
	Jan. 06, 2017	Dec. 16, 2016	Apr. 05, 2016	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Gain (loss) on sale of property
Gain (loss) on sale of property				$ (20,492)	$ (643)	$ (18,203)	$ (643)
Office Property in Baltimore Maryland
Gain (loss) on sale of property
Provision for loss on property held				$ 20,500
Office Property In Milpitas, California \| Disposal Group, Held-for-sale or Disposed of by Sale, Not Discontinued Operations
Gain (loss) on sale of property
Gain (loss) on sale of property	$ 2,300
Office Property In Maryland Heights Missouri \| Disposal Group, Held-for-sale or Disposed of by Sale, Not Discontinued Operations
Gain (loss) on sale of property
Gain (loss) on sale of property			$ 4,200
Office Property In Federal Way Washington \| Disposal Group, Held-for-sale or Disposed of by Sale, Not Discontinued Operations
Gain (loss) on sale of property
Gain (loss) on sale of property		$ (7,100)
Net Proceeds		$ 7,300