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Indebtedness - Narrative (Details) | 1 Months Ended | 12 Months Ended |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
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Jun. 30, 2018 USD ($) property | Mar. 31, 2018 USD ($) building property | Feb. 28, 2018 USD ($) property | Dec. 31, 2018 USD ($) property building note | Dec. 31, 2017 USD ($) property | Dec. 31, 2016 USD ($) property | Feb. 27, 2019 USD ($) | Sep. 30, 2018 USD ($) property | Jul. 31, 2018 USD ($) property | Jan. 31, 2018 USD ($) property | Jun. 30, 2017 USD ($) property | May 31, 2017 USD ($) property | Apr. 30, 2017 USD ($) property | Mar. 31, 2017 | Oct. 31, 2016 USD ($) property | Sep. 30, 2016 USD ($) property | Jul. 31, 2016 USD ($) building property | Apr. 30, 2016 USD ($) property | Feb. 29, 2016 USD ($) | Jan. 31, 2016 USD ($) property | Dec. 31, 2015 USD ($) | Dec. 31, 2014 USD ($)
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of debt |  |  |  | $ 2,250,000,000 | $ 1,750,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Mortgage debt assumed |  |  |  | 44,386,000 | 0 | $ 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Real estate property, gross |  |  |  | 7,876,300,000 | 7,824,763,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Capital leases |  |  |  | 9,800,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unsecured revolving credit facility |  |  |  | 139,000,000 | 596,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss on early extinguishment of debt |  |  |  | (22,000) | $ (7,627,000) | $ (526,000) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unsecured revolving credit facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unsecured revolving credit facility, maximum borrowing capacity |  |  |  | $ 1,000,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of public issues of unsecured senior notes | note |  |  |  | 7 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maximum borrowing capacity that may be increased |  |  |  | $ 2,000,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revolving credit facility, interest rate payable (as a percent) |  |  |  | 3.60% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average interest rate on debt (as a percent) |  |  |  | 3.00% | 2.40% | 1.80% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unsecured revolving credit facility |  |  |  | $ 139,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revolving credit facility, available amount |  |  |  | $ 861,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior unsecured notes due 2019 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate (as a percent) |  |  |  | 3.25% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maximum borrowing capacity that may be increased |  |  |  | $ 400,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Unsecured Notes 6.75 Percent Due 2020 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of debt |  |  |  | $ 200,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate (as a percent) |  |  |  | 6.75% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unsecured senior notes due 2021 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of debt |  |  |  | $ 300,000,000 | $ 300,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate (as a percent) |  |  |  | 6.75% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior unsecured notes due 2024 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of debt |  |  |  | $ 250,000,000 | 250,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate (as a percent) |  |  |  | 4.75% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Unsecured Notes Due 2028 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of debt |  |  | $ 500,000,000 | $ 500,000,000 | 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate (as a percent) |  |  | 4.75% | 4.75% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior unsecured notes 5.625% due in 2042 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of debt |  |  |  | $ 350,000,000 | 350,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate (as a percent) |  |  |  | 5.625% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior unsecured notes due in 2046 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of debt |  |  |  | $ 250,000,000 | $ 250,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 250,000,000 |  |  |
Interest rate (as a percent) |  |  |  | 6.25% |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 6.25% |  |  |
Unsecured Notes Due June 2023 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate (as a percent) |  |  | 6.64% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Mortgage debt assumed |  |  | $ 16,748,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unsecured Notes Due June 2023 | Senior Living Communities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of properties mortgaged | property |  |  | 1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unsecured Notes Due July 2043 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate (as a percent) |  | 4.44% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Mortgage debt assumed |  | $ 11,050,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unsecured Notes Due July 2043 | MOBs |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of properties mortgaged | property |  | 1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of buildings mortgaged | building |  | 1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Notes Due October 2022 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate (as a percent) | 5.75% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Mortgage debt assumed | $ 16,588,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Notes Due October 2022 | Senior Living Communities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of properties mortgaged | property | 2 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Term loan due 2020 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 350,000,000
Interest rate (as a percent) |  |  |  | 3.70% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maximum borrowing capacity that may be increased |  |  |  | $ 700,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average interest rate on debt (as a percent) |  |  |  | 3.40% | 2.50% | 1.90% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest expense and other associated costs incurred |  |  |  | $ 12,555,000 | $ 9,338,000 | $ 7,231,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Term loan due 2020 | LIBOR |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis points per annum (as a percent) |  |  |  | 1.40% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Term loan due 2022 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 200,000,000 |
Interest rate (as a percent) |  |  |  | 3.90% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average interest rate on debt (as a percent) |  |  |  | 3.40% | 2.70% | 2.30% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest expense and other associated costs incurred |  |  |  | $ 7,095,000 | $ 5,756,000 | $ 4,889,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Term loan due 2022 | LIBOR |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis points per annum (as a percent) |  |  |  | 1.35% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Mortgages |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Secured debt |  |  |  | $ 734,748,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of properties mortgaged | property |  |  |  | 13 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of buildings mortgaged | building |  |  |  | 14 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Real estate property, gross |  |  |  | $ 1,034,799,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Capital leases |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Real estate property, gross |  |  |  | $ 34,568,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of properties recorded under capital lease | property |  |  |  | 2 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Capital leases |  |  |  | $ 9,832,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Secured debt financing due 2026 | MOBs |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Secured debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 620,000,000 |  |  |  |  |
Number of properties mortgaged | property |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1 |  |  |  |  |
Number of buildings mortgaged | building |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2 |  |  |  |  |
Weighted average interest rate on debt (as a percent) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3.53% |  |  |  |  |
Mortgage maturing in September 2043 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate (as a percent) |  |  |  |  |  |  |  |  |  | 4.40% |  |  |  |  |  |  |  |  |  |  |  |
Secured debt |  |  |  |  |  |  |  |  |  | $ 4,338,000 |  |  |  |  |  |  |  |  |  |  |  |
Number of properties mortgaged | property |  |  |  |  |  |  |  |  |  | 1 |  |  |  |  |  |  |  |  |  |  |  |
Senior Unsecured Notes Due October 2018 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of debt |  |  |  |  |  |  |  |  | $ 90,602,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Number of properties mortgaged | property |  |  |  |  |  |  |  |  | 12 |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average interest rate on debt (as a percent) |  |  |  |  |  |  |  |  | 5.00% |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Unsecured Notes Due January 2019 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of debt |  |  |  |  |  |  |  | $ 6,325,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate (as a percent) |  |  |  |  |  |  |  | 4.70% |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of properties mortgaged | property |  |  |  |  |  |  |  | 1 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Unsecured Notes Due September 2019 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of debt |  |  |  |  |  |  |  |  |  |  |  |  | $ 5,449,000 |  |  |  |  |  |  |  |  |
Interest rate (as a percent) |  |  |  |  |  |  |  |  |  |  |  |  | 6.71% |  |  |  |  |  |  |  |  |
Secured debt |  |  |  |  |  |  |  |  |  |  |  |  | $ 277,837,000 |  |  |  |  |  |  |  |  |
Number of properties mortgaged | property |  |  |  |  |  |  |  |  |  |  |  |  | 17 |  |  |  |  |  |  |  |  |
Senior Unsecured Notes Due August 2017 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate (as a percent) |  |  |  |  |  |  |  |  |  |  |  | 6.15% |  |  |  |  |  |  |  |  |  |
Secured debt |  |  |  |  |  |  |  |  |  |  |  | $ 10,579,000 |  |  |  |  |  |  |  |  |  |
Number of properties mortgaged | property |  |  |  |  |  |  |  |  |  |  |  | 1 |  |  |  |  |  |  |  |  |  |
Senior Unsecured Notes Due August 2037 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate (as a percent) |  |  |  |  |  |  |  |  |  |  | 5.95% |  |  |  |  |  |  |  |  |  |  |
Secured debt |  |  |  |  |  |  |  |  |  |  | $ 8,807,000 |  |  |  |  |  |  |  |  |  |  |
Number of properties mortgaged | property |  |  |  |  |  |  |  |  |  |  | 1 |  |  |  |  |  |  |  |  |  |  |
Senior Unsecured Notes Due April 2018 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate (as a percent) |  |  |  |  | 6.73% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Secured debt |  |  |  |  | $ 8,403,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of properties mortgaged | property |  |  |  |  | 1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Unsecured Notes Due April 2016 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate (as a percent) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 5.97% |  |
Secured debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 6,115,000 |  |
Number of properties mortgaged | property |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1 |  |
Senior Unsecured Notes Due July 2016 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate (as a percent) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 4.65% |  |  |  |
Secured debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 18,000,000 |  |  |  |
Number of properties mortgaged | property |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1 |  |  |  |
Senior Unsecured Notes Due November 2016 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate (as a percent) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 6.25% |  |  |  |  |
Secured debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 79,957,000 | $ 11,871,000 |  |  |  |  |
Number of properties mortgaged | property |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2 | 1 |  |  |  |  |
Weighted average interest rate on debt (as a percent) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 5.92% |  |  |  |  |  |
Senior Unsecured Notes Due May 2017 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 42,542,000 |  |  |  |  |  |  |
Number of properties mortgaged | property |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 8 |  |  |  |  |  |  |
Weighted average interest rate on debt (as a percent) |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 6.54% |  |  |  |  |  |  |
Senior Unsecured Notes Due March 2017 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate (as a percent) |  |  |  |  |  | 5.86% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Secured debt |  |  |  |  |  | $ 5,428,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of properties mortgaged | property |  |  |  |  |  | 1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revolving Credit Facility | Unsecured revolving credit facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest expense and other associated costs incurred |  |  |  | $ 10,348,000 | $ 14,346,000 | $ 13,100,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revolving Credit Facility | Unsecured revolving credit facility | LIBOR |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis points per annum (as a percent) |  |  |  | 1.20% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loan commitment fee percentage |  |  |  | 0.25% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Joint Venture |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ownership interest by parent |  |  |  |  |  |  |  |  |  |  |  |  |  | 55.00% |  |  |  |  |  |  |  |
Joint Venture | Secured debt financing due 2026 | MOBs |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ownership interest by parent |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 55.00% |  |  |  |  |
Subsequent Event | Unsecured revolving credit facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unsecured revolving credit facility |  |  |  |  |  |  | $ 238,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revolving credit facility, available amount |  |  |  |  |  |  | $ 762,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

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