Leases and Management Agreements with Five Star - Narrative (Details) - Five Star $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($) lease_agreement community	Mar. 31, 2018 USD ($) community	Dec. 31, 2018 USD ($)
Number of communities leased by the Company \| community	184	185
Number of leases with related party \| lease_agreement	5
Total rental income recognized	$ 39,313	$ 51,759
Related party transaction, annual rents due	538	1,374
Rents receivable	22,000		$ 18,697
Real estate improvements purchased	22,579
Property management agreement expense	$ 3,789	$ 3,494
Rents from significant lessee \| Investment
Percentage of rental income	26.50%
Senior Living Communities
Number of communities managed by related party \| community	76	72
Rehabilitation Services
Expenses from transactions with related party	$ 1,675	$ 1,699
Rental income \| Rents from significant lessee \| Investment
Percentage of rental income	14.80%

Represents the number of communities managed by a related party.

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Number of Communities Leased by the Company

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Number of Leases With Related Party

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Represents the amount of improvements to real estate properties made by lessees and purchased by the entity.

+ References

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Related Party Transaction, Annual Rents Due

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Expenses recognized during the period resulting from property management transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party during the period.

+ References

No definition available.

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- Definition

Represents rents receivable at the balance sheet date.

+ References

No definition available.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of transactions with related party during the financial reporting period.

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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