Quarterly Financial Data (Unaudited) - Unaudited Quarterly Financial Information (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Quarterly Financial Information [Line Items]
Revenues	$ 256,438	$ 224,756	$ 192,549	$ 180,454	$ 180,578	$ 196,996	$ 201,902	$ 205,046	$ 854,197	$ 784,522	$ 704,745
Net income	129,923	90,267	79,920	76,291	78,941	736,476	112,017	91,043	376,401	1,018,477	291,238
Net income attributable to MPT common stockholders (Operating Partnership partners)	$ 129,638	$ 89,786	$ 79,438	$ 75,822	$ 78,483	$ 736,034	$ 111,567	$ 90,601	$ 374,684	$ 1,016,685	$ 289,793
Net income attributable to MPT common stockholders (Operating Partnership partners)	$ 0.26	$ 0.20	$ 0.20	$ 0.20	$ 0.21	$ 2.01	$ 0.30	$ 0.25	$ 0.87	$ 2.77	$ 0.82
Weighted average shares (units) outstanding — basic	493,593	439,581	394,574	380,551	366,655	365,024	364,897	364,882	427,075	365,364	349,902
Net income attributable to MPT common stockholders (Operating Partnership partners)	$ 0.26	$ 0.20	$ 0.20	$ 0.20	$ 0.21	$ 2.00	$ 0.30	$ 0.25	$ 0.87	$ 2.76	$ 0.82
Weighted average shares (units) outstanding — diluted	494,893	440,933	395,692	381,675	367,732	366,467	365,541	365,343	428,299	366,271	350,441
MPT Operating Partnership, L.P. [Member]
Quarterly Financial Information [Line Items]
Revenues	$ 256,438	$ 224,756	$ 192,549	$ 180,454	$ 180,578	$ 196,996	$ 201,902	$ 205,046	$ 854,197	$ 784,522	$ 704,745
Net income	129,923	90,267	79,920	76,291	78,941	736,476	112,017	91,043	376,401	1,018,477	291,238
Net income attributable to MPT common stockholders (Operating Partnership partners)	$ 129,638	$ 89,786	$ 79,438	$ 75,822	$ 78,483	$ 736,034	$ 111,567	$ 90,601	$ 374,684	$ 1,016,685	$ 289,793
Net income attributable to MPT common stockholders (Operating Partnership partners)	$ 0.26	$ 0.20	$ 0.20	$ 0.20	$ 0.21	$ 2.01	$ 0.30	$ 0.25	$ 0.87	$ 2.77	$ 0.82
Weighted average shares (units) outstanding — basic	493,593	439,581	394,574	380,551	366,655	365,024	364,897	364,882	427,075	365,364	349,902
Net income attributable to MPT common stockholders (Operating Partnership partners)	$ 0.26	$ 0.20	$ 0.20	$ 0.20	$ 0.21	$ 2.00	$ 0.30	$ 0.25	$ 0.87	$ 2.76	$ 0.82
Weighted average shares (units) outstanding — diluted	494,893	440,933	395,692	381,675	367,732	366,467	365,541	365,343	428,299	366,271	350,441