Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=68055307&loc=d3e2420-110228

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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- Definition

The net gain (loss) resulting from sales and other disposals of real estate owned for investment purposes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.14(d))
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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- Definition

The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.

+ 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)
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- Definition

Carrying amount as of the balance sheet date of investments in land and buildings held for sale, excluding real estate considered to be inventory of the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(f))
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- Definition

Revenue from the sale of commercial, industrial, or residential property during the period. This element is more likely than not relevant to an entity for which real estate operations are a principal activity. If real estate operations are not a principal activity, the reporting entity would likely use a gain (loss) on sale of property, plant, or equipment type element.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(e))
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Gain Loss On Sale Of Other Assets and Liabilities.

+ References

No definition available.

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This represents the number of the properties which are classified as held for sale.

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No definition available.

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Real property dispositions.

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Dispositions, Assets Held for Sale and Discontinued Operations (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018 USD ($) properties	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) properties	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)
Real property dispositions:
Total dispositions			$ 829,749	$ 927,512
Gain (loss) on real estate dispositions, net	$ 24,723	$ 1,622	373,662	287,869
Net other assets/liabilities disposed			5,090	22,470
Proceeds from sales of real property			1,208,501	1,237,851
Real estate held-for-sale	619,141		619,141		$ 734,147
Impairment of assets	$ 6,740	$ 0	39,557	24,662
Triple Net
Real property dispositions:
Total dispositions			$ 604,480	899,104
Number of properties classified as held for sale \| properties	60		60
Senior housing - operating
Real property dispositions:
Total dispositions			$ 2,200	16,206
Number of properties classified as held for sale \| properties	16		16
Outpatient Medical
Real property dispositions:
Total dispositions			$ 223,069	$ 12,202
Number of properties classified as held for sale \| properties	3		3