For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6351-108592

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13531-108611

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
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-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13537-108611

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592

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Real Estate and Lending Activities - Alecto Facilities - Additional Information (Detail)	3 Months Ended		9 Months Ended
	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($) Property	Sep. 30, 2019 USD ($) Property	Sep. 30, 2018 USD ($)	Aug. 07, 2019 USD ($) Facility
Business Acquisition [Line Items]
Real estate impairment charge			$ 7,232,000	$ 17,615,000
Rent revenue	$ 31,026,000	$ 18,293,000	$ 76,813,000	$ 49,157,000
Alecto Healthcare Services [Member]
Business Acquisition [Line Items]
Number of leased properties \| Property		4	4
Number of facilities closed \| Facility					2
Investment in closed facilities					$ 30,000,000
Real estate impairment charge		$ 30,000,000
Rent revenue	$ 0
Alecto Healthcare Services [Member] \| Total Gross Assets [Member] \| Customer Concentration Risk [Member] \| Maximum [Member]
Business Acquisition [Line Items]
Percentage of Total Gross Assets			1.00%