Earnings Per Share/Unit - Calculation of Earnings Per Share (Detail) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Net income	$ 81,157	$ 76,291
Non-controlling interests’ share in net income	(165)	(469)
Participating securities’ share in earnings	(464)	(476)
Net income, less participating securities’ share in earnings	$ 80,528	$ 75,346
Basic weighted-average common shares	521,076	380,551
Dilutive potential common shares	1,103	1,124
Dilutive weighted-average common shares	522,179	381,675
MPT Operating Partnership, L.P. [Member]
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Net income	$ 81,157	$ 76,291
Non-controlling interests’ share in net income	(165)	(469)
Participating securities’ share in earnings	(464)	(476)
Net income, less participating securities’ share in earnings	$ 80,528	$ 75,346
Basic weighted-average common shares	521,076	380,551
Dilutive potential common shares	1,103	1,124
Dilutive weighted-average common shares	522,179	381,675