Segment Information (Capital Expenditures) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Segment Reporting Information
Total capital expenditures	$ 1,802,021	$ 607,296	$ 1,518,772
Operating Segments | Triple-net leased properties
Segment Reporting Information
Total capital expenditures	92,924	42,930	55,429
Operating Segments | Senior living operations
Segment Reporting Information
Total capital expenditures	1,463,551	191,891	944,214
Operating Segments | Office operations
Segment Reporting Information
Total capital expenditures	$ 245,546	$ 372,475	$ 519,129