Earnings Per Share/Unit - Calculation of Earnings Per Share (Detail) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2021	Jun. 30, 2020
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Net income	$ 114,821	$ 163,880	$ 109,652	$ 81,157	$ 278,701	$ 190,809
Non-controlling interests’ share in net income	(256)		(184)		(353)	(349)
Participating securities’ share in earnings	(390)		(487)		(760)	(951)
Net income, less participating securities’ share in earnings	$ 114,175		$ 108,981		$ 277,588	$ 189,509
Basic weighted-average common shares	587,514		527,781		581,877	524,428
Dilutive potential common shares	1,539		1,099		1,420	1,102
Diluted weighted-average common shares	589,053		528,880		583,297	525,530
MPT Operating Partnership, L.P. [Member]
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Net income	$ 114,821	$ 163,880	$ 109,652	$ 81,157	$ 278,701	$ 190,809
Non-controlling interests’ share in net income	(256)		(184)		(353)	(349)
Participating securities’ share in earnings	(390)		(487)		(760)	(951)
Net income, less participating securities’ share in earnings	$ 114,175		$ 108,981		$ 277,588	$ 189,509
Basic weighted-average common shares	587,514		527,781		581,877	524,428
Dilutive potential common shares	1,539		1,099		1,420	1,102
Diluted weighted-average common shares	589,053		528,880		583,297	525,530