Segment Information (Capital Expenditures) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information
Total capital expenditures	$ 1,518,772	$ 728,641	$ 1,096,327
Operating Segments | Triple Net Leased Properties
Segment Reporting Information
Total capital expenditures	55,429	58,744	254,542
Operating Segments | Senior Living Operations
Segment Reporting Information
Total capital expenditures	944,214	337,750	261,900
Operating Segments | Office Operations
Segment Reporting Information
Total capital expenditures	$ 519,129	$ 332,147	$ 579,885