Earnings Per Share/Unit - Calculation of Earnings Per Share (Detail) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Net income	$ 171,395	$ 114,821	$ 163,880	$ 131,357	$ 109,652	$ 81,157	$ 450,096	$ 322,166
Non-controlling interests’ share in net income	(258)			(251)			(611)	(600)
Participating securities’ share in earnings	(328)			(435)			(1,088)	(1,386)
Net income, less participating securities’ share in earnings	$ 170,809			$ 130,671			$ 448,397	$ 320,180
Basic weighted-average common shares	595,119			531,095			586,291	526,651
Dilutive potential common shares	2,201			1,341			1,680	1,181
Diluted weighted-average common shares	597,320			532,436			587,971	527,832
MPT Operating Partnership, L.P. [Member]
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Net income	$ 171,395	$ 114,821	$ 163,880	$ 131,357	$ 109,652	$ 81,157	$ 450,096	$ 322,166
Non-controlling interests’ share in net income	(258)			(251)			(611)	(600)
Participating securities’ share in earnings	(328)			(435)			(1,088)	(1,386)
Net income, less participating securities’ share in earnings	$ 170,809			$ 130,671			$ 448,397	$ 320,180
Basic weighted-average common shares	595,119			531,095			586,291	526,651
Dilutive potential common shares	2,201			1,341			1,680	1,181
Diluted weighted-average common shares	597,320			532,436			587,971	527,832