Dispositions (Details) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2015 USD ($) building	Jun. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)
Disposal Group, Not Discontinued Operation, Disposal Disclosures [Abstract]
Number of MOBs disposed | building	6
Aggregate gross sales price of disposed medical office buildings	$ 35,700
Gain from sale of disposed medical office buildings	152		$ 11,766	$ 152	$ 11,766
Impairment charge on medical office building marketed for sale	$ 0	$ 1,655	$ 0	$ 1,655	$ 0