Real Estate and Lending Activities - Alecto Facilities - Additional Information (Detail) - Alecto Healthcare Services [Member] $ in Millions	3 Months Ended
Mar. 31, 2020 USD ($) Facility Property
Business Acquisition [Line Items]
Number of leased properties \| Property	4
Number of facilities donated \| Facility	1
Real estate impairment charge \| $	$ 9.1
Total Gross Assets [Member] \| Customer Concentration Risk [Member] \| Maximum [Member]
Business Acquisition [Line Items]
Percentage of total assets	0.50%

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.

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