Earnings Per Share/Unit - Calculation of Earnings Per Share (Detail) - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Net income	$ 656,940	$ 432,272	$ 376,401
Non-controlling interests’ share in earnings	(919)	(822)	(1,717)
Participating securities’ share in earnings	(2,161)	(2,105)	(2,308)
Net income, less participating securities’ share in earnings	$ 653,860	$ 429,345	$ 372,376
Basic weighted-average common shares	588,817	529,239	427,075
Dilutive potential common shares	1,322	1,222	1,224
Diluted weighted-average common shares	590,139	530,461	428,299
MPT Operating Partnership, L.P. [Member]
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Net income	$ 656,940	$ 432,272	$ 376,401
Non-controlling interests’ share in earnings	(919)	(822)	(1,717)
Participating securities’ share in earnings	(2,161)	(2,105)	(2,308)
Net income, less participating securities’ share in earnings	$ 653,860	$ 429,345	$ 372,376
Basic weighted-average common shares	588,817	529,239	427,075
Dilutive potential common shares	1,322	1,222	1,224
Diluted weighted-average common shares	590,139	530,461	428,299