Common Stock/Partners' Capital - Additional Information (Detail) $ / shares in Units, $ in Thousands					3 Months Ended	12 Months Ended
	Nov. 13, 2017 USD ($)	May 01, 2017 USD ($) shares	Oct. 07, 2016 USD ($) $ / shares shares	Sep. 30, 2016 USD ($) shares	Dec. 31, 2018 USD ($) shares	Dec. 31, 2018 USD ($) Partner Employee shares	Dec. 31, 2017 USD ($) shares	Dec. 31, 2016 USD ($) shares
Class of Stock [Line Items]
Proceeds from sale of common shares / units, net of offering costs					$ 95	$ 94,239	$ 547,785	$ 1,173,651
Common stock, shares issued | shares					370,637,000	370,637,000	364,424,000
Redemption of common units						$ 816
Employee [Member]
Class of Stock [Line Items]
Number of partners shared remaining ownership percentage | Employee						2
MPT Operating Partnership, L.P. [Member]
Class of Stock [Line Items]
Proceeds from sale of common shares / units, net of offering costs						$ 94,239	$ 547,785	1,173,651
Percentage of ownership of general partner						100.00%
Number of other partners | Partner						2
Redemption of common units						$ 816
MPT Operating Partnership, L.P. [Member] | Medical Properties Trust, Inc. [Member]
Class of Stock [Line Items]
Ownership interest in equity					99.90%	99.90%
Market Equity Offering Program [Member]
Class of Stock [Line Items]
Proceeds from sale of common shares / units, net of offering costs								224,000
Sales commissions, amount								$ 2,800
Market Equity Offering Program [Member] | Maximum [Member]
Class of Stock [Line Items]
Value of stock	$ 750,000
Sales commission percentage	2.00%
Public Offering [Member]
Class of Stock [Line Items]
Proceeds from sale of common shares / units, net of offering costs		$ 548,000		$ 799,500
Common stock, shares issued | shares		43,100,000		57,500,000
Additional shares purchased by underwriters | shares		5,600,000		7,500,000
Common Units [Member]
Class of Stock [Line Items]
Number of share sold | shares					5,600	5,614,000	43,125,000	82,749,000
Common Units [Member] | MPT Operating Partnership, L.P. [Member] | Limited Partner [Member]
Class of Stock [Line Items]
Number of share sold | shares						5,558,000	42,694,000	81,918,000
Conversion of LTIP units to common units | shares						60,000
Redemption of common units						$ 816
Common Units [Member] | Market Equity Offering Program [Member]
Class of Stock [Line Items]
Number of share sold | shares							0	15,000,000
Common Units [Member] | Private Placement [Member] | Cerberus Capital Management [Member]
Class of Stock [Line Items]
Number of share sold | shares			10,300,000
Proceeds from sale of common shares / units, net of offering costs			$ 150,000
Sale of Stock, price per share | $ / shares			$ 14.50