Segment Reporting - Narratives (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($) segment	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Segment Reporting Information
Number of business segments | segment	2
Disposition of goodwill	$ 34,273
Real Estate
Segment Reporting Information
Gross contract revenue	11,399	$ 50,220	$ 28,072
Disposition of goodwill	0
Real Estate | Hotel in Bloomington, MN
Segment Reporting Information
Gross contract revenue	4,000	15,000	15,200
Real Estate | Miami, FL
Segment Reporting Information
Gross contract revenue	1,900	14,400	1,700
Real Estate | Hotel in Memphis, TN
Segment Reporting Information
Gross contract revenue			4,800
Investment Management
Segment Reporting Information
Gross contract revenue	31,322	$ 59,903	$ 106,607
Disposition of goodwill	$ 34,273