Difference between amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee.

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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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Amount of expenses related to the managing member or general partner for management of the day-to-day business functions of the limited liability company (LLC) or limited partnership (LP).

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The number of real estate properties owned as of the balance sheet date.

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Payments to develop real estate assets is the process of adding improvements on or to a parcel of land. Such improvements may include drainage, utilities, subdividing, access, buildings, and any combination of these elements; and are generally classified as cash flow from investing activities.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Expected Additional Payments To Develop Real Estate Assets

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Percent of net assets at close of period including new acquisitions. For schedules of investments that are categorized, each category has a percent of net assets for the aggregated value of the Investments in the category.

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Investments in Unconsolidated Entities (Narrative) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($) property	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Schedule of Equity Method Investments [Line Items]
Income (loss) from unconsolidated entities	$ (8,083)	$ 42,434	$ (641)
Aggregate unamortized basis difference of joint venture investments	116,504
Loans related to development and construction of certain properties	333,934
Additional fund obligated related to investments	$ 120,004
VIE
Schedule of Equity Method Investments [Line Items]
Number of real estate properties \| property	8
Sunrise
Schedule of Equity Method Investments [Line Items]
Investment percentage including new acquisition		34.00%
Management fees	$ 40,088	$ 41,200	$ 36,378
Sunrise \| Minimum
Schedule of Equity Method Investments [Line Items]
Option renewal periods	5 years
Sunrise \| Maximum
Schedule of Equity Method Investments [Line Items]
Option renewal periods	15 years
Seniors Housing Operating
Schedule of Equity Method Investments [Line Items]
Income (loss) from unconsolidated entities		$ 38,681