Subsequent Events - Additional Information (Detail) $ / shares in Units, € in Millions								1 Months Ended	6 Months Ended
	Aug. 06, 2015 USD ($) shares	Aug. 05, 2015 USD ($) Hospital	Aug. 04, 2015 USD ($) $ / shares shares	Jul. 30, 2015 USD ($)	Jul. 27, 2015 USD ($)	Jan. 14, 2015 USD ($) shares	Mar. 11, 2014 USD ($) shares	Jul. 31, 2015 USD ($) Facility Leases	Jun. 30, 2015 USD ($) $ / shares shares	Jun. 30, 2014 USD ($)	Jul. 31, 2015 EUR (€) Facility	Dec. 31, 2014 $ / shares shares
Subsequent Event [Line Items]
Common stock, shares issued | shares									207,804,000			172,743,000
Proceeds from sale of common shares/units, net of offering costs									$ 479,902,000	$ 128,332,000
Common stock, shares authorized | shares									250,000,000			250,000,000
Common stock, par value | $ / shares									$ 0.001			$ 0.001
Public Offering [Member]
Subsequent Event [Line Items]
Common stock, shares issued | shares						34,500,000	7,700,000
Proceeds from sale of common shares/units, net of offering costs						$ 480,000,000	$ 100,200,000
Net proceeds from additional issuance of shares							$ 16,000,000
Subsequent Event [Member]
Subsequent Event [Line Items]
Common stock, shares authorized | shares			500,000,000
Common stock, par value | $ / shares			$ 0.001
Subsequent Event [Member] | Capella Healthcare, Inc. [Member]
Subsequent Event [Line Items]
Interests acquired, number of hospitals | Facility								5
Combined purchase price and investment amount								$ 900,000,000
Acquisition costs								$ 390,000,000
Number of hospitals used to secure loans | Facility								2			2
Secured loans granted in connection with acquisition								$ 210,000,000
Merger consideration net of real estate investments								300,000,000
Merger consideration in the form of acquisition loan								$ 290,000,000
Ownership interests acquired								49.00%			49.00%
Term of lease, years								15 years
Number of lease extension options | Leases								4
Term of lease extension, years								5 years
Increase in consumer price-index, floor rate								2.00%
Increase in consumer price-index, ceiling rate								4.00%
Aggregate committed size of credit facility			$ 1,250,000,000
Senior unsecured bridge loan facility, maturity period					364 days
Subsequent Event [Member] | Texas [Member]
Subsequent Event [Line Items]
Proceeds from sale of real estate				$ 9,700,000
Gain (loss) on sale of real estate				1,500,000
Straight line rent receivables write-off				$ 900,000
Subsequent Event [Member] | United States
Subsequent Event [Line Items]
Proceeds from sale of real estate		$ 9,500,000
Number of hospitals sold | Hospital		6
Consideration received as note receivable		$ 1,500,000
Subsequent Event [Member] | Bridge Loan [Member] | Capella Healthcare, Inc. [Member]
Subsequent Event [Line Items]
Aggregate committed size of credit facility					$ 1,000,000,000
Increase (decrease) in credit facility	$ (600,000,000)		(100,000,000)
Remaining borrowing capacity			$ 900,000,000
Subsequent Event [Member] | Public Offering [Member] | Capella Healthcare, Inc. [Member]
Subsequent Event [Line Items]
Common stock, shares issued | shares	28,750,000
Proceeds from sale of common shares/units, net of offering costs	$ 337,100,000
Net proceeds from additional issuance of shares	$ 3,800,000
Subsequent Event [Member] | LIBOR Rate [Member] | Minimum [Member] | Bridge Loan [Member] | Capella Healthcare, Inc. [Member]
Subsequent Event [Line Items]
Interest rate, applicable margin					1.025%
Subsequent Event [Member] | LIBOR Rate [Member] | Maximum [Member] | Bridge Loan [Member] | Capella Healthcare, Inc. [Member]
Subsequent Event [Line Items]
Interest rate, applicable margin					2.25%
Subsequent Event [Member] | Base Rate [Member] | Minimum [Member] | Bridge Loan [Member] | Capella Healthcare, Inc. [Member]
Subsequent Event [Line Items]
Interest rate, applicable margin					0.025%
Subsequent Event [Member] | Base Rate [Member] | Maximum [Member] | Bridge Loan [Member] | Capella Healthcare, Inc. [Member]
Subsequent Event [Line Items]
Interest rate, applicable margin					1.25%
Subsequent Event [Member] | Capella Management [Member] | Capella Healthcare, Inc. [Member]
Subsequent Event [Line Items]
Ownership interests acquired								51.00%			51.00%
Subsequent Event [Member] | Acute Care Hospital [Member]
Subsequent Event [Line Items]
Purchase price of acquisition | €											€ 90
Ownership interest percentage, parent								50.00%			50.00%
Subsequent Event [Member] | Acute Care Hospital [Member] | Capella Healthcare, Inc. [Member]
Subsequent Event [Line Items]
Interests acquired, number of hospitals | Facility								7