schedule of net revenue, operating loss from operations and assets (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Segment Reporting Information [Line Items]
Total operating loss	$ (1.0)	$ (0.8)
Interest expense	0.1	0.1
Other income, net		0.1
Loss from operations before income taxes	(1.1)	(0.8)
Total consolidated assets	14.1		$ 14.6
Operating Segments [Member]
Segment Reporting Information [Line Items]
Total net revenue	0.1
Total operating loss	(0.3)	(0.4)
Total consolidated assets	13.8		13.5
Operating Segments [Member] | Asset Management Business [Member]
Segment Reporting Information [Line Items]
Total net revenue	0.1
Total operating loss	(0.3)	(0.4)
Interest expense	(0.1)	(0.1)
Other income, net		0.1
Loss from operations before income taxes	(1.1)	(0.8)
Total consolidated assets	13.8		13.5
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Total operating loss	(0.7)	$ (0.4)
Total consolidated assets	$ 0.3		$ 1.1