Acquisitions, Dispositions and New Construction - Additional Information (Detail)	1 Months Ended		2 Months Ended	3 Months Ended				9 Months Ended		12 Months Ended
	May 31, 2015 USD ($) ft² Property	Feb. 28, 2015 USD ($) ft² Building	Feb. 28, 2015 USD ($) ft² Property	Sep. 30, 2016 USD ($) ft² Time	Jun. 30, 2016 USD ($) ft²	Mar. 31, 2016 USD ($) ft² Time	Sep. 30, 2015 USD ($) $ / shares	Sep. 30, 2016 USD ($) ft² Time	Sep. 30, 2015 USD ($) $ / shares	Dec. 31, 2015 USD ($)
Business Acquisitions And Dispositions [Line Items]
Total cash paid								$ 52,200,000
Deposits on real estate assets								420,000
Business combination recorded aggregate net revenue				$ 723,000				1,100,000
Business combination aggregate net losses generated by properties including cost of borrowings and advisory fee expenses				47,000				134,000
Business acquisition, pro forma net revenues				$ 17,200,000			$ 16,400,000	51,700,000	$ 50,100,000
Business Acquisition, pro forma net income							$ 3,400,000		$ 18,700,000
Business Acquisition, pro forma diluted per share | $ / shares							$ 0.25		$ 1.40
Cash received for property exchange transaction								$ 0	$ 2,000,000
Gain on property exchange									8,742,000
Universal Health Services, Inc
Business Acquisitions And Dispositions [Line Items]
Number of term renewal options | Time				6				6
Additional renewal terms								5 years
Henderson Medical Plaza | Universal Health Services, Inc
Business Acquisitions And Dispositions [Line Items]
Maximum amount of investment for development and construction						$ 21,100,000
Amount invested in MOB under construction				$ 4,600,000				$ 4,600,000
Ground lease agreement period						75 years
Number of term renewal options | Time						2
Additional renewal terms						10 years
Sheffield Medical Building
Business Acquisitions And Dispositions [Line Items]
Net rentable area | ft²	36,700
Cash received for property exchange transaction	$ 2,000,000
Area of disposed building | ft²	73,446
Number of assets acquired | Property	2
Percentage of rentable area covered by the agreement	100.00%
Lease agreement period	15 years
Percentage of annual rent increase	3.00%
Gain on property exchange									8,700,000
Minimum
Business Acquisitions And Dispositions [Line Items]
Acquired intangible assets include in-place leases amortization period								6 years
Maximum
Business Acquisitions And Dispositions [Line Items]
Acquired intangible assets include in-place leases amortization period								12 years
Frederick Memorial Hospital Crestwood
Business Acquisitions And Dispositions [Line Items]
Total purchase price				$ 24,300,000
Net rentable area | ft²				62,300				62,300
Frederick Memorial Hospital Crestwood | Lease Agreements
Business Acquisitions And Dispositions [Line Items]
Renewal Term (years)				12 years
Chandler Corporate Center III
Business Acquisitions And Dispositions [Line Items]
Total purchase price					$ 18,000,000
Net rentable area | ft²					82,000
Occupied percentage of property					92.00%
Lease rent escalation period					12 years
Lessor Leasing Arrangements, Operating Leases, Renewal Term					10 years
Chandler Corporate Center III | Lease Agreements
Business Acquisitions And Dispositions [Line Items]
Renewal Term (years)					11 years 3 months 18 days
Madison Professional Office Building
Business Acquisitions And Dispositions [Line Items]
Total purchase price						$ 10,100,000
Net rentable area | ft²						30,100
Deposits on real estate assets										$ 150,000
Madison Professional Office Building | Lease Agreements
Business Acquisitions And Dispositions [Line Items]
Renewal Term (years)						6 years 2 months 12 days
Haas Medical Office Park
Business Acquisitions And Dispositions [Line Items]
Total purchase price		$ 4,100,000
Net rentable area | ft²		16,000	16,000
Number of Buildings purchased | Building		2
Wholly Owned Subsidiaries Of U H S Real Property Of Two Newly Constructed And Recently Opened F E Ds Located In Weslaco And Mission Texas
Business Acquisitions And Dispositions [Line Items]
Total purchase price			$ 12,800,000
Additional renewal terms			5 years
Cash received for property exchange transaction									$ 0
Number of real properties purchased | Property			2
Lease agreement period			10 years
Wholly Owned Subsidiaries Of U H S Real Property Of Two Newly Constructed And Recently Opened F E Ds Located In Weslaco And Mission Texas | Recently Opened Free Standing Emergency Departments | Weslaco
Business Acquisitions And Dispositions [Line Items]
Area of acquired building | ft²		13,600	13,600
Wholly Owned Subsidiaries Of U H S Real Property Of Two Newly Constructed And Recently Opened F E Ds Located In Weslaco And Mission Texas | Recently Opened Free Standing Emergency Departments | Mission
Business Acquisitions And Dispositions [Line Items]
Area of acquired building | ft²		13,600	13,600