Limited Liability Companies Accounted for Under Equity Method (Parenthetical) (Detail) - USD ($)	1 Months Ended	3 Months Ended	12 Months Ended
	Oct. 31, 2015	Dec. 31, 2015	Dec. 31, 2015
Brunswick Associates
Schedule Of Equity Method Investments [Line Items]
Third-party term loan		$ 8,800,000	$ 8,800,000
Arlington Medical Properties
Schedule Of Equity Method Investments [Line Items]
Committed investment in equity and debt financing, funded		5,200,000	5,200,000
Commitment to investment		1,100,000	$ 1,100,000
Proceeds from Lines of Credit	$ 22,800,000	$ 22,800,000
Percentage of minority ownership purchased from third-party members		10.00%	10.00%
Business acquisition additional consideration		$ 4,800,000	$ 4,800,000
Cash payment made purchased addition of ownership interest			85.00%
Grayson Properties
Schedule Of Equity Method Investments [Line Items]
Third-party term loan		14,700,000	$ 14,700,000
Committed investment in equity and debt financing, funded		2,800,000	2,800,000
Commitment to investment		149,000	149,000
FTX MOB Phase II limited partnership
Schedule Of Equity Method Investments [Line Items]
Third-party term loan		5,400,000	5,400,000
Committed investment in equity and debt financing, funded		1,500,000	1,500,000
Commitment to investment		$ 2,500,000	$ 2,500,000