Investment in Real Estate - Narratives (Details) $ in Thousands		3 Months Ended	12 Months Ended
	Jan. 23, 2019 USD ($) property site	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($) property site	Dec. 31, 2019 USD ($) property site	Dec. 31, 2018 USD ($) property
Real Estate Properties
Purchase price			$ 209,200		$ 251,700
Mortgage debt assumed			6,900
Long-term debt assumed				$ 18,600	9,200
Mortgage premium transferred				600
Assets acquired			248,100	249,197	265,129
Asset acquisition, liabilities incurred					8,800
Gain on sale of real estate, net			$ 0	$ 52,507	$ 0
Disposed of by Sale, Not Discontinued Operations | Manufactured Homes in Indiana and Michigan
Real Estate Properties
Number of properties sold (property) | property	5
Number of sites sold | site	1,463
Proceeds from sales of properties	$ 89,700
Gain on sale of real estate, net		$ 52,500
Net investment in real estate	35,400
Other assets	500
Mortgage notes payable	$ 11,200
M H Resorts
Real Estate Properties
Number of properties acquired | property			1		4
Number of sites acquired			2,772		3,712
R V Resort
Real Estate Properties
Number of properties acquired | property			7	4	4
Purchase price				$ 58,300
Number of sites acquired | site				1,614
Marinas
Real Estate Properties
Number of properties acquired | property			1	11
Developmental Properties
Real Estate Properties
Number of properties acquired | property			3
Purchase price			$ 23,700
Land
Real Estate Properties
Number of properties acquired | property			9	3
Purchase price			$ 15,200	$ 28,100
Loggerhead
Real Estate Properties
Purchase price				49,000
Repayments of outstanding debt				72,000
Assets acquired				162,200
Loggerhead | Joint venture
Real Estate Properties
Assets acquired				$ 35,800
Vacant Land
Real Estate Properties
Number of properties acquired | property					2
Purchase price					$ 2,800