Schedule of Indebtedness (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Carrying Value		$ 1,588,799
Fixed rate debt
Debt Instrument [Line Items]
Mortgages payable and other notes payable		382,129	$ 391,639
Variable Rate Debt
Debt Instrument [Line Items]
Mortgages payable and other notes payable	[1]	561,874	449,017
Mortgage Loans | Fixed rate debt
Debt Instrument [Line Items]
Mortgages payable and other notes payable		$ 382,129	391,639
Mortgage Loans | Pacific Northwest II Communities
Debt Instrument [Line Items]
Interest on Loan accrues - Fixed rate	[2],[3]	4.30%
Payment Terms	[3]	Monthly principal and interest payments based on a 25-year amortization schedule
Principal and interest payments amortizable period	[3]	25 years
Maturity Date	[3],[4]	Dec. 05, 2018
Mortgage Loans | Pacific Northwest II Communities | Fixed rate debt
Debt Instrument [Line Items]
Mortgages payable and other notes payable	[3]	$ 205,197	210,665
Mortgage Loans | Capital Health Communities
Debt Instrument [Line Items]
Interest on Loan accrues - Fixed rate	[2]	4.25%
Payment Terms		Monthly principal and interest payments based on a 25-year amortization schedule
Principal and interest payments amortizable period		25 years
Maturity Date	[4]	Jan. 05, 2020
Mortgage Loans | Capital Health Communities | Fixed rate debt
Debt Instrument [Line Items]
Mortgages payable and other notes payable		$ 36,395	37,889
Mortgage Loans | Primrose II Communities
Debt Instrument [Line Items]
Interest on Loan accrues - Fixed rate	[2]	3.81%
Payment Terms		Monthly principal and interest payments based on a 30-year amortization schedule
Principal and interest payments amortizable period		30 years
Maturity Date	[4]	Jun. 01, 2020
Mortgage Loans | Primrose II Communities | Fixed rate debt
Debt Instrument [Line Items]
Mortgages payable and other notes payable		$ 22,017	22,473
Mortgage Loans | Novi Orthopaedic Center
Debt Instrument [Line Items]
Interest on Loan accrues - Fixed rate	[2]	3.61%
Payment Terms		Monthly interest only payments through June 2018; principal and interest payments thereafter based on a 25-year amortization schedule
Principal and interest payments amortizable period		25 years
Interest payments ending date		2018-06
Maturity Date	[4]	Jun. 15, 2020
Mortgage Loans | Novi Orthopaedic Center | Fixed rate debt
Debt Instrument [Line Items]
Mortgages payable and other notes payable		$ 19,825	19,825
Mortgage Loans | ProMed Building I
Debt Instrument [Line Items]
Interest on Loan accrues - Fixed rate	[2],[5]	3.64%
Payment Terms		Monthly principal and interest payments based upon a 25-year amortization schedule
Principal and interest payments amortizable period		25 years
Maturity Date	[4]	Jan. 15, 2022
Mortgage Loans | ProMed Building I | Fixed rate debt
Debt Instrument [Line Items]
Mortgages payable and other notes payable		$ 6,865	7,050
Mortgage Loans | Primrose I Communities
Debt Instrument [Line Items]
Interest on Loan accrues - Fixed rate	[2],[6]	4.11%
Payment Terms	[6]	Monthly principal and interest payments based on a 30-year amortization schedule
Principal and interest payments amortizable period	[6]	30 years
Maturity Date	[4],[6]	Sep. 01, 2022
Mortgage Loans | Primrose I Communities | Fixed rate debt
Debt Instrument [Line Items]
Mortgages payable and other notes payable	[6]	$ 51,000	52,048
Mortgage Loans | Watercrest at Mansfield
Debt Instrument [Line Items]
Interest on Loan accrues - Fixed rate	[2],[7]	4.68%
Payment Terms	[7]	Monthly principal and interest payments based on a total payment of $143,330
Maturity Date	[4],[7]	Jun. 01, 2023
Mortgage Loans | Watercrest at Mansfield | Fixed rate debt
Debt Instrument [Line Items]
Mortgages payable and other notes payable	[7]	$ 26,165	26,628
Mortgage Loans | 540 New Waverly Place
Debt Instrument [Line Items]
Interest on Loan accrues - Fixed rate	[2],[8]	4.08%
Payment Terms	[8]	Monthly principal and interest payments based upon a 25-year amortization schedule
Principal and interest payments amortizable period	[8]	25 years
Maturity Date	[4],[8]	May 31, 2028
Mortgage Loans | 540 New Waverly Place | Fixed rate debt
Debt Instrument [Line Items]
Mortgages payable and other notes payable	[8]	$ 6,868	7,048
Mortgage Loans | LaPorte Cancer Center Westville, Indiana
Debt Instrument [Line Items]
Interest on Loan accrues - Fixed rate	[2]	4.25%
Payment Terms		Monthly principal and interest payments based on a 25-year amortization schedule
Principal and interest payments amortizable period		25 years
Maturity Date	[4]	Jun. 14, 2028
Mortgage Loans | LaPorte Cancer Center Westville, Indiana | Fixed rate debt
Debt Instrument [Line Items]
Mortgages payable and other notes payable		$ 7,797	8,013
Mortgage Loans | Lee Hughes Medical Building
Debt Instrument [Line Items]
Payment Terms		Monthly principal and interest payments based on a 30-year amortization schedule
Principal and interest payments amortizable period		30 years
Maturity Date	[4]	Sep. 05, 2016
Mortgage Loans | Lee Hughes Medical Building | Variable Rate Debt
Debt Instrument [Line Items]
Mortgages payable and other notes payable		$ 18,102	18,632
Mortgage Loans | Northwest Medical Park
Debt Instrument [Line Items]
Payment Terms	[9]	Monthly principal and interest payments based upon a 25-year amortization schedule
Principal and interest payments amortizable period	[9]	25 years
Maturity Date	[4],[9]	Oct. 31, 2017
Mortgage Loans | Northwest Medical Park | Variable Rate Debt
Debt Instrument [Line Items]
Mortgages payable and other notes payable	[9]	$ 6,886	7,008
Mortgage Loans | Claremont Medical Office
Debt Instrument [Line Items]
Payment Terms	[10]	Monthly principal and interest payments based on a 30-year amortization schedule
Principal and interest payments amortizable period	[10]	30 years
Maturity Date	[4],[10]	Jan. 16, 2018
Mortgage Loans | Claremont Medical Office | Variable Rate Debt
Debt Instrument [Line Items]
Mortgages payable and other notes payable	[10]	$ 12,478	12,683
Mortgage Loans | Knoxville MOBs
Debt Instrument [Line Items]
Payment Terms	[11]	Monthly interest only payments for the first 18 months; principal and interest payments thereafter based on a 30-year amortization schedule
Principal and interest payments amortizable period	[11]	30 years
Maturity Date	[4],[11]	Jul. 10, 2018
Mortgage Loans | Knoxville MOBs | Variable Rate Debt
Debt Instrument [Line Items]
Mortgages payable and other notes payable	[11]	$ 37,491	38,087
Mortgage Loans | Calvert Medical Office Properties
Debt Instrument [Line Items]
Payment Terms	[12]	Monthly interest only payments for the first 18 months; principal and interest payments thereafter based on a 30-year amortization schedule
Principal and interest payments amortizable period	[12]	30 years
Maturity Date	[4],[12]	Aug. 29, 2018
Mortgage Loans | Calvert Medical Office Properties | Variable Rate Debt
Debt Instrument [Line Items]
Mortgages payable and other notes payable	[12]	$ 25,546	25,950
Mortgage Loans | MHOSH MOB
Debt Instrument [Line Items]
Payment Terms	[13]	Monthly principal and interest payments based on a 25-year amortization schedule
Principal and interest payments amortizable period	[13]	25 years
Maturity Date	[4],[13]	Jun. 02, 2019
Mortgage Loans | MHOSH MOB | Variable Rate Debt
Debt Instrument [Line Items]
Mortgages payable and other notes payable	[13]	$ 47,983	48,832
Mortgage Loans | Medical Portfolio II
Debt Instrument [Line Items]
Payment Terms	[14]	Monthly principal and interest payments based on a 25-year amortization schedule
Principal and interest payments amortizable period	[14]	25 years
Maturity Date	[4],[14]	Jul. 14, 2019
Mortgage Loans | Medical Portfolio II | Variable Rate Debt
Debt Instrument [Line Items]
Mortgages payable and other notes payable	[14]	$ 81,365	83,295
Mortgage Loans | Southeast Medical Office Properties
Debt Instrument [Line Items]
Payment Terms	[15]	Monthly principal and interest payments based on a 25-year amortization schedule
Principal and interest payments amortizable period	[15]	25 years
Maturity Date	[4],[15]	Dec. 22, 2019
Mortgage Loans | Southeast Medical Office Properties | Variable Rate Debt
Debt Instrument [Line Items]
Mortgages payable and other notes payable	[15]	$ 155,090	160,206
Mortgage Loans | Palmilla Senior Living
Debt Instrument [Line Items]
Payment Terms		Interest only payments through April 2017; principal payments thereafter based on a 30-year amortization schedule
Principal and interest payments amortizable period		30 years
Interest payments ending date		2017-04
Maturity Date	[4]	Mar. 22, 2020
Mortgage Loans | Palmilla Senior Living | Variable Rate Debt
Debt Instrument [Line Items]
Mortgages payable and other notes payable		$ 27,000
Mortgage Loans | Triangle Orthopaedic
Debt Instrument [Line Items]
Payment Terms		Interest only payments through March 2017; principal payments thereafter based on a 30-year amortization schedule
Principal and interest payments amortizable period		30 years
Interest payments ending date		2017-03
Maturity Date	[4]	Apr. 11, 2021
Mortgage Loans | Triangle Orthopaedic | Variable Rate Debt
Debt Instrument [Line Items]
Mortgages payable and other notes payable		$ 37,800
Mortgage Loans | Cobalt Rehabilitation Hospital Surprise
Debt Instrument [Line Items]
Payment Terms		Monthly interest only payments through May 2017; principal payments thereafter based on a 25-year amortization schedule
Principal and interest payments amortizable period		25 years
Interest payments ending date		2017-05
Maturity Date	[4]	May 19, 2022
Mortgage Loans | Cobalt Rehabilitation Hospital Surprise | Variable Rate Debt
Debt Instrument [Line Items]
Mortgages payable and other notes payable		$ 15,379
Mortgage Loans | Cobalt Rehabilitation Hospital New Orleans
Debt Instrument [Line Items]
Payment Terms		Monthly interest only payments through October 2017; principal payments thereafter based on a 25-year amortization schedule
Principal and interest payments amortizable period		25 years
Interest payments ending date		2017-10
Maturity Date	[4]	Oct. 19, 2022
Mortgage Loans | Cobalt Rehabilitation Hospital New Orleans | Variable Rate Debt
Debt Instrument [Line Items]
Mortgages payable and other notes payable		$ 19,500
Construction Loan | Variable Rate Debt
Debt Instrument [Line Items]
Mortgages payable and other notes payable		$ 13,542
Construction Loan | Raider Ranch Development | Variable Rate Debt
Debt Instrument [Line Items]
Mortgages payable and other notes payable			7,528
Construction Loan | Watercrest at Katy
Debt Instrument [Line Items]
Payment Terms		Monthly interest only payments through December 2017
Maturity Date	[4]	Dec. 27, 2017
Construction Loan | Watercrest at Katy | Variable Rate Debt
Debt Instrument [Line Items]
Mortgages payable and other notes payable		$ 24,047	10,632
Construction Loan | Wellmore of Tega Cay | Variable Rate Debt
Debt Instrument [Line Items]
Mortgages payable and other notes payable			23,695
Construction Loan | HarborChase Of Shorewood (Shorewood, Wisconsin)
Debt Instrument [Line Items]
Payment Terms		Monthly interest only payments through June 2017; principal and interest payments thereafter based on a 25-year amortization schedule
Principal and interest payments amortizable period		25 years
Interest payments ending date		2017-06
Maturity Date	[4]	Jul. 15, 2019
Construction Loan | HarborChase Of Shorewood (Shorewood, Wisconsin) | Variable Rate Debt
Debt Instrument [Line Items]
Mortgages payable and other notes payable		$ 14,755	12,469
Construction Loan | Wellmore of Lexington (Lexington, SC)
Debt Instrument [Line Items]
Payment Terms		Monthly interest only payments through September 2019
Interest payments ending date		2019-09
Maturity Date	[4]	Sep. 13, 2019
Construction Loan | Waterstone on Augusta (Greenville, SC)
Debt Instrument [Line Items]
Payment Terms		Monthly interest only payments through September 2018; principal payments thereafter based on a 30-year amortization schedule
Principal and interest payments amortizable period		30 years
Interest payments ending date		2018-09
Maturity Date	[4]	Sep. 01, 2020
Construction Loan | Waterstone on Augusta (Greenville, SC) | Variable Rate Debt
Debt Instrument [Line Items]
Mortgages payable and other notes payable		$ 12,698
Construction Loan | Fieldstone at Pear Orchard (Yakima, Washington)
Debt Instrument [Line Items]
Payment Terms		Monthly interest only payments through September 2018; principal payments thereafter based on a 25-year amortization schedule
Principal and interest payments amortizable period		25 years
Interest payments ending date		2018-09
Maturity Date	[4]	Oct. 15, 2020
Construction Loan | Fieldstone at Pear Orchard (Yakima, Washington) | Variable Rate Debt
Debt Instrument [Line Items]
Mortgages payable and other notes payable		$ 8,861
Construction Loan | The Dogwood Forest of Grayson (Grayson, GA)
Debt Instrument [Line Items]
Payment Terms		Monthly interest only payments through December 2018; principal payments thereafter based on a 30-year amortization schedule
Principal and interest payments amortizable period		30 years
Interest payments ending date		2018-12
Maturity Date	[4]	Dec. 01, 2020
Construction Loan | The Dogwood Forest of Grayson (Grayson, GA) | Variable Rate Debt
Debt Instrument [Line Items]
Mortgages payable and other notes payable		$ 3,351
Mortgage And Construction Loans
Debt Instrument [Line Items]
Carrying Value		944,003	840,656
Mortgage And Construction Loans | Variable Rate Debt
Debt Instrument [Line Items]
Mortgages payable and other notes payable		$ 561,874	$ 449,017
30-day LIBOR | Mortgage Loans | Lee Hughes Medical Building
Debt Instrument [Line Items]
Interest accrues on loan in addition to LIBOR	[2]	1.85%
30-day LIBOR | Mortgage Loans | Northwest Medical Park
Debt Instrument [Line Items]
Interest accrues on loan in addition to LIBOR	[2],[9]	2.30%
30-day LIBOR | Mortgage Loans | Claremont Medical Office
Debt Instrument [Line Items]
Interest accrues on loan in addition to LIBOR	[2],[10]	2.60%
30-day LIBOR | Mortgage Loans | Knoxville MOBs
Debt Instrument [Line Items]
Interest accrues on loan in addition to LIBOR	[2],[11]	2.50%
30-day LIBOR | Mortgage Loans | Calvert Medical Office Properties
Debt Instrument [Line Items]
Interest accrues on loan in addition to LIBOR	[2],[12]	2.50%
30-day LIBOR | Mortgage Loans | MHOSH MOB
Debt Instrument [Line Items]
Interest accrues on loan in addition to LIBOR	[2],[13]	2.85%
Payment Terms	[2],[13]	0.40%
30-day LIBOR | Mortgage Loans | Medical Portfolio II
Debt Instrument [Line Items]
Interest accrues on loan in addition to LIBOR	[2],[14]	2.35%
Payment Terms	[2],[14]	0.25%
30-day LIBOR | Mortgage Loans | Southeast Medical Office Properties
Debt Instrument [Line Items]
Interest accrues on loan in addition to LIBOR	[2],[15]	2.00%
30-day LIBOR | Mortgage Loans | Palmilla Senior Living
Debt Instrument [Line Items]
Interest accrues on loan in addition to LIBOR	[2]	2.00%
30-day LIBOR | Mortgage Loans | Triangle Orthopaedic
Debt Instrument [Line Items]
Interest accrues on loan in addition to LIBOR	[2]	2.25%
30-day LIBOR | Mortgage Loans | Cobalt Rehabilitation Hospital Surprise
Debt Instrument [Line Items]
Interest accrues on loan in addition to LIBOR	[2]	2.60%
Payment Terms		0.40%
30-day LIBOR | Mortgage Loans | Cobalt Rehabilitation Hospital New Orleans
Debt Instrument [Line Items]
Interest accrues on loan in addition to LIBOR	[2]	2.45%
Payment Terms		0.55%
30-day LIBOR | Construction Loan
Debt Instrument [Line Items]
Interest accrues on loan in addition to LIBOR	[2]	2.50%
30-day LIBOR | Construction Loan | Watercrest at Katy
Debt Instrument [Line Items]
Interest accrues on loan in addition to LIBOR	[2]	2.75%
30-day LIBOR | Construction Loan | HarborChase Of Shorewood (Shorewood, Wisconsin)
Debt Instrument [Line Items]
Interest accrues on loan in addition to LIBOR	[2]	3.00%
30-day LIBOR | Construction Loan | Waterstone on Augusta (Greenville, SC)
Debt Instrument [Line Items]
Interest accrues on loan in addition to LIBOR	[2]	3.00%
30-day LIBOR | Construction Loan | Fieldstone at Pear Orchard (Yakima, Washington)
Debt Instrument [Line Items]
Interest accrues on loan in addition to LIBOR	[2]	2.90%
30-day LIBOR | Construction Loan | The Dogwood Forest of Grayson (Grayson, GA)
Debt Instrument [Line Items]
Interest accrues on loan in addition to LIBOR	[2]	3.00%

[1] As of December 31, 2016 and 2015, the Company had entered into interest rate swaps with notional amounts of approximately $521.5 million and $480.7 million, respectively, which were settling on a monthly basis. In addition, as of December 31, 2015, the Company had entered into forward-starting interest rate swaps for total notional amounts of approximately $48.4 million in order to hedge its exposure to variable rate debt beginning in June 2016. Refer to Note 12. “Derivative Financial Instruments” for additional information.

[2] The 30-day and 90-day LIBOR were approximately 0.77% and 1.00%, respectively, as of December 31, 2016 and approximately 0.43% and 0.61%, respectively, as of December 31, 2015.

[3] The Pacific Northwest Loan may be prepaid, in whole or in part, with a prepayment premium equal to the greater of: (i) one percent (1%) of the principal amount being prepaid, multiplied by the quotient of the number of full months remaining until the maturity date of the loan (calculated as of the prepayment date) divided by the number of full months comprising the term of the loan; or (b) a “make-whole” payment equal to the present value of the loan less the amount of principal and accrued interest being prepaid calculated as of the prepayment date for the period between that date and the maturity date.

[4] Represents the initial maturity date (or, as applicable, the maturity date as extended). Certain of the Company’s mortgages and other notes payable agreements include extension options held by the Company under which the maturity dates may be extended beyond the date presented, subject to certain lender conditions and/or related fees.

[5] Beginning January 2020, the interest rate transitions to variable rate based on 30-day LIBOR plus 2.20% per annum.

[6] If prepaid prior to March 1, 2022, the Primrose I Communities Mortgage Loan is subject to a prepayment penalty in an amount equal to the greater of (i) 1% of the principal being repaid, or (ii) an amount calculated on the principal being repaid, multiplied by the difference between the Primrose I Communities Mortgage Loan interest rate, and a calculated yield rate tied to the rates on applicable U.S. Treasuries. If prepayment is made between March 1, 2022, and May 31, 2022, the prepayment penalty will be 1% of the outstanding principal balance of the Primrose I Communities Mortgage Loan. No prepayment fee is required if the Primrose I Communities Mortgage Loan is prepaid between June 1, 2022 and maturity. Partial prepayment of a loan is not permitted. The loan is transferable upon sale of the assets subject to lender approval.

[7] The balance for this loan excludes a remaining premium of $0.3 million related to the mortgage note payable assumed being recorded at fair value on the acquisition date.

[8] The balance for this loan excludes a remaining premium of $0.1 million related to the mortgage note payable assumed being recorded at fair value on the acquisition date.

[9] The Company entered into an interest rate swap with a remaining notional amount of $6.9 million; see Note 12. “Derivative Financial Instruments” for additional information

[10] The balance for this loan excludes a remaining discount of $0.2 million related to the mortgage note payable assumed being recorded at fair value on the acquisition date. In addition, the Company entered into a three-year forward interest rate swap with a remaining notional amount of $12.1 million; see Note 12. “Derivative Financial Instruments” for additional information.

[11] The Company entered into an interest rate swap with a remaining notional amount of $37.4 million; see Note 12. “Derivative Financial Instruments” for additional information.

[12] The Company entered into an interest rate swap with a remaining notional amount of $25.5 million; see Note 12. “Derivative Financial Instruments” for additional information.

[13] The Company entered into a three-year forward interest rate swap with a remaining notional amount of $48.0 million; see Note 12. “Derivative Financial Instruments” for additional information.

[14] The Company entered into an interest rate swap with a remaining notional amount of $82.4 million; see Note 12. “Derivative Financial Instruments” for additional information.

[15] The Company entered into an interest rate swap with a remaining notional amount of $134.3 million; see Note 12. “Derivative Financial Instruments” for additional information.