Intangibles net - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2016 USD ($) Office	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Finite-Lived Intangible Assets And Liabilities [Line Items]
Amortization expense on intangible assets	$ 45,300	$ 44,600	$ 25,100
Amortization expense on intangible liabilities	$ 1,700	1,600	800
Number of medical office of anchor tenant bankruptcy | Office	2
Loss on lease terminations	$ (785)	(863)
Impairment provision of intangible assets		4,700
Rental Income from Operating Leases
Finite-Lived Intangible Assets And Liabilities [Line Items]
Amortization expense on intangible assets	2,000	2,000	1,000
Amortization expense on intangible liabilities	1,600	1,500	800
Property Operating Expenses
Finite-Lived Intangible Assets And Liabilities [Line Items]
Amortization expense on intangible assets	300	300	100
Amortization expense on intangible liabilities	100	80	8
Depreciation And Amortization
Finite-Lived Intangible Assets And Liabilities [Line Items]
Amortization expense on intangible assets	$ 43,000	$ 42,300	$ 24,000