Condensed Combined Statement of Income for Limited Liabilities Accounted for under Equity Method (Parenthetical) (Detail) - USD ($)	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017
Arlington Medical Properties
Schedule Of Equity Method Investments [Line Items]
Interest income earned on various advances made to LLCs	$ 0	$ 284,000

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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