Common Stock/Partners' Capital - Additional Information (Detail) shares in Thousands, $ in Thousands		3 Months Ended
	May 10, 2019 USD ($) shares	Mar. 31, 2019 USD ($) Employee shares	Mar. 31, 2018 USD ($)
Class Of Stock [Line Items]
Proceeds from sale of common shares / units, net of offering costs | $		$ 354,030	$ (94)
MPT Operating Partnership, L.P. [Member]
Class Of Stock [Line Items]
Number of units sold		20,100
MPT Operating Partnership, L.P. [Member] | Medical Properties Trust, Inc. [Member]
Class Of Stock [Line Items]
Ownership interest in equity		99.90%
Employee [Member]
Class Of Stock [Line Items]
Number of partners shared remaining ownership percentage | Employee		2
Subsequent Event [Member]
Class Of Stock [Line Items]
Proceeds from sale of common shares / units, net of offering costs | $	$ 45,000
Common Units [Member]
Class Of Stock [Line Items]
Number of share sold		20,147
Common Units [Member] | Subsequent Event [Member]
Class Of Stock [Line Items]
Number of share sold	2,500