Other Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Straight-line rent receivables	$ 278,833
Straight-line rent receivables		$ 250,023
Non-mortgage loans receivable, net	63,724	54,164
Marketable debt securities	237,360	206,442
Other intangible assets, net	5,149	5,623
Investment in unconsolidated operating entities	59,301	56,820
Other	232,929	186,113
Total other assets	$ 877,296	$ 759,185