Summary of Significant Accounting Policies - Additional Information (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2015 USD ($) Property State	Dec. 31, 2014 USD ($) Property	Dec. 31, 2013 USD ($)	Aug. 01, 2014 Property	Jan. 01, 2014 Property
Significant Accounting Policies [Line Items]
Number of real estate investments	62
Number of states that real estate investments are located | State	18
Intangible assets, estimated aggregate amortization expenses for 2016 | $	$ 4.6
Intangible assets, estimated aggregate amortization expenses for 2017 | $	4.0
Intangible assets, estimated aggregate amortization expenses for 2018 | $	2.7
Intangible assets, estimated aggregate amortization expenses for 2019 | $	2.0
Intangible assets, estimated aggregate amortization expenses for 2020 | $	1.8
Amortization expense, intangible assets | $	5.5	$ 6.1	$ 6.0
Depreciation expense | $	$ 16.2	$ 14.4	$ 12.5
Percentage of minority ownership interests by parent		100.00%
Federal excise tax rate when amount of 85% of ordinary income plus 95% of any capital gain income exceeds cash distributions	4.00%
Gross cost basis of properties for federal income tax purposes | $	$ 489.0
Net book value of the properties for federal income tax purposes | $	325.0
Net gain on fair value recognition resulting from the purchase of minority interests in majority-owned LLCs | $	$ 25.4
Palmdale Medical Properties and Sparks Medical Properties
Significant Accounting Policies [Line Items]
Number of real estate investments					2
Percentage of minority ownership purchased from third-party members				5.00%	5.00%
Percentage of minority ownership interests by parent	100.00%			100.00%
In Place Leases
Significant Accounting Policies [Line Items]
Intangible asset, useful life	4 years 1 month 6 days
Minimum
Significant Accounting Policies [Line Items]
Non-controlling equity interest, ownership percentage	33.00%
Percentage of minority ownership purchased from third-party members				5.00%
Percentage of real estate investment taxable income that should be distributed to remain exempt from federal income taxes	90.00%
Maximum
Significant Accounting Policies [Line Items]
Non-controlling equity interest, ownership percentage	95.00%
Percentage of minority ownership purchased from third-party members				15.00%
Buildings | Minimum
Significant Accounting Policies [Line Items]
Estimated original useful lives of property plant and equipment	25 years
Buildings | Maximum
Significant Accounting Policies [Line Items]
Estimated original useful lives of property plant and equipment	45 years
Capital Improvements | Minimum
Significant Accounting Policies [Line Items]
Estimated original useful lives of property plant and equipment	3 years
Capital Improvements | Maximum
Significant Accounting Policies [Line Items]
Estimated original useful lives of property plant and equipment	35 years
Limited Liability Companies
Significant Accounting Policies [Line Items]
Number of real estate investments		8		6	6
Limited Liability Companies | Palmdale Medical Properties and Sparks Medical Properties
Significant Accounting Policies [Line Items]
Percentage of minority ownership interests by parent				100.00%
Limited Liability Companies | Minimum
Significant Accounting Policies [Line Items]
Percentage of minority ownership purchased from third-party members				5.00%
Limited Liability Companies | Maximum
Significant Accounting Policies [Line Items]
Percentage of minority ownership purchased from third-party members				15.00%
Hospitals
Significant Accounting Policies [Line Items]
Number of real estate investments	6
Hospitals | Acute Care
Significant Accounting Policies [Line Items]
Number of real estate investments	3
Hospitals | Rehabilitation
Significant Accounting Policies [Line Items]
Number of real estate investments	1
Hospitals | Sub-acute
Significant Accounting Policies [Line Items]
Number of real estate investments	2
Mission and Weslaco Freestanding Emergency Departments
Significant Accounting Policies [Line Items]
Number of real estate investments	3
Medical office buildings
Significant Accounting Policies [Line Items]
Number of real estate investments	49
Medical office buildings | Majority Owned Subsidiary Unconsolidated
Significant Accounting Policies [Line Items]
Number of real estate investments	5
Medical office buildings | Limited Liability Companies
Significant Accounting Policies [Line Items]
Number of real estate investments	5
Preschool and childcare Centers
Significant Accounting Policies [Line Items]
Number of real estate investments	4