Real Estate Activities - 2016 Activity - Additional Information (Detail) $ in Thousands, € in Millions						1 Months Ended	12 Months Ended
		Oct. 21, 2016 USD ($) Hospital RenewalOption	Oct. 03, 2016 USD ($) Hospital RenewalOption Facility	Jul. 22, 2016 USD ($)	May 02, 2016 USD ($)	Sep. 30, 2015 USD ($)	Dec. 31, 2018 USD ($) Hospital	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($) Hospital	Dec. 31, 2016 EUR (€) Hospital	Jun. 22, 2016 EUR (€)
Business Acquisition [Line Items]
Loans repaid	[1]						$ 764,447		$ 193,262
Mortgage financing							50,783	$ 717,928	612,836
Mortgage financing funded							$ 615,764		310,000
Capella [Member]
Business Acquisition [Line Items]
Loans repaid									$ 93,300
Rehabilitation Hospital with Covenant Health System [Member] | Germany [Member]
Business Acquisition [Line Items]
Number of facilities acquired | Hospital							3
2016 [Member] | Olympia, Washington [Member] | Capella [Member]
Business Acquisition [Line Items]
Cash paid for acquisition transaction				$ 7,000
Loans repaid				$ 93,300
2016 [Member] | New Jersey [Member] | Acute Care Hospital [Member]
Business Acquisition [Line Items]
Acquisition costs					$ 63,000
Commitment to advance an additional amount for capital additions					$ 30,000
Commitment period to advance an additional amount for capital additions					3 years
2016 [Member] | Rehabilitation Hospital with Covenant Health System [Member] | Germany [Member]
Business Acquisition [Line Items]
Number of facilities acquired | Hospital									12	12
Acquisition costs | €										€ 85.2
2016 [Member] | General Acute Care Hospital and Healthcare System [Member]
Business Acquisition [Line Items]
Term of lease, years		15 years
Number of lease extension options | RenewalOption		3
Number of facilities acquired | Hospital		3
Lease agreement, end date		2031-05
Number of free-standing emergency department and health center | Hospital		1
Mortgage financing						$ 100,000
Mortgage financing funded		$ 15,000
2016 [Member] | 2015 Master Lease [Member] | Rehabilitation Hospital with Covenant Health System [Member] | Germany [Member]
Business Acquisition [Line Items]
Number of facilities acquired | Hospital									5	5
Acquisition costs | €										€ 35.6
2016 [Member] | Third Master Lease [Member] | Rehabilitation Hospital with Covenant Health System [Member] | Germany [Member]
Business Acquisition [Line Items]
Number of facilities acquired | Hospital									7	7
Acquisition costs | €										€ 49.5
Lease agreement, end date									2043-08	2043-08
Term of lease									27 years
2016 [Member] | Steward [Member]
Business Acquisition [Line Items]
Number of hospitals closed | Hospital			9
Combined purchase price and investment amount			$ 1,250,000
Number of licensed hospitals | Hospital			5
Cash paid for acquisition transaction			$ 600,000
Loans repaid			600,000
Equity interest acquired			$ 50,000
Term of lease, years			15 years
Number of lease extension options | RenewalOption			3
Number of facilities for making mortgage loans | Facility			4
Lease expiration date			Oct. 31, 2031
2016 [Member] | MEDIAN [Member]
Business Acquisition [Line Items]
Value of properties closed | €											€ 41.6

[1] The 2018 column includes $0.8 billion of loans advanced to Steward in 2016 and repaid in 2018 as part of sale leaseback conversion described below. The 2016 column includes $93.3 million of loans advanced to Capella(2) in 2015 and repaid in 2016 as a part of the Capella transaction (2), along with $100.0 million of loans advanced to Prime Healthcare Services, Inc. (“Prime”) in 2015 and repaid in 2016 as part of the sale leaseback conversion of four properties in New Jersey.