Investment in Real Estate - Real Estate by Property Type and Segment (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Real Estate Properties [Line Items]
Development property	$ 159,427,000		$ 159,427,000		$ 161,252,000
Operating property	217,905,000		217,905,000		216,416,000
Less: Accumulated depreciation	67,090,000		67,090,000		64,069,000
Total operating property, net	150,815,000		150,815,000		152,347,000
Investment in real estate, net	310,242,000		310,242,000		313,599,000
Capitalized indirect costs incurred	0	$ 100,000	0	$ 100,000.0
Residential real estate
Real Estate Properties [Line Items]
Development property	96,731,000		96,731,000		99,413,000
Operating property	8,091,000		8,091,000		8,091,000
Commercial real estate
Real Estate Properties [Line Items]
Development property	56,586,000		56,586,000		56,587,000
Resorts and leisure
Real Estate Properties [Line Items]
Operating property	109,556,000		109,556,000		109,425,000
Leasing operations
Real Estate Properties [Line Items]
Development property	1,120,000		1,120,000		360,000
Operating property	81,024,000		81,024,000		79,550,000
Forestry
Real Estate Properties [Line Items]
Development property	2,606,000		2,606,000		2,681,000
Operating property	19,184,000		19,184,000		19,300,000
Other
Real Estate Properties [Line Items]
Operating property	50,000		50,000		50,000
Corporate
Real Estate Properties [Line Items]
Development property	$ 2,384,000		$ 2,384,000		$ 2,211,000