Amount of assets held-for-sale that are not part of a disposal group.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 15
-Paragraph 4
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=77912953&loc=d3e400-110220

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- Definition

The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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- References

No definition available.

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- Definition

Amount of loss contingency liability.

+ 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=82911808&loc=d3e14326-108349

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- Definition

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

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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=98514028&loc=d3e3179-108585

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Dispositions of Properties (Details) - USD ($) $ in Thousands					1 Months Ended	3 Months Ended		12 Months Ended
	Oct. 20, 2017	Jan. 06, 2017	Dec. 16, 2016	Apr. 05, 2016	Jun. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Jun. 30, 2017
Gain (loss) on sale of property
Gain (loss) on sale of property								$ (18,481)	$ (2,938)
Disposal Group, Held-for-sale or Disposed of by Sale, Not Discontinued Operations \| Office Property In Federal Way Washington
Gain (loss) on sale of property
Assets Held-for-sale, Not Part of Disposal Group					$ 9,300		$ 8,800
Provision for loss on property held					$ 4,800		500
Gain (loss) on sale of property							$ 5,300
Disposal Group, Held-for-sale or Disposed of by Sale, Not Discontinued Operations \| Office Property in Baltimore Maryland
Gain (loss) on sale of property
Assets Held-for-sale, Not Part of Disposal Group						$ 31,600				$ 31,900
Loss contingency on property held						20,700				$ 20,500
Provision for loss on property held						$ 300
Disposal group disposed of by sale, not classified as discontinued operations \| Office Property In Milpitas, California
Gain (loss) on sale of property
Gain (loss) on sale of property		$ 2,300
Disposal group disposed of by sale, not classified as discontinued operations \| Office Property In Maryland Heights Missouri
Gain (loss) on sale of property
Gain (loss) on sale of property				$ 4,200
Disposal group disposed of by sale, not classified as discontinued operations \| Office Property In Federal Way Washington
Gain (loss) on sale of property
Gain (loss) on sale of property			$ (7,100)
Net Proceeds			$ 7,300
Disposal group disposed of by sale, not classified as discontinued operations \| Office Property in Baltimore Maryland
Gain (loss) on sale of property
Gain (loss) on sale of property	$ (20,800)
Net Proceeds	$ 31,600