Segmented Information - Segment (loss) income (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Segment Reporting Information [Line Items]
Total segment operating income	$ (828)	$ (1,519)	$ (1,727)	$ (2,218)
Net investment income	749	1,010	1,448	1,648
Net realized gains	(556)	132	(241)	397
(Loss) gain on change in fair value of equity investments	(63)	(421)	15	744
Gain (loss) on change in fair value of limited liability investments, at fair value	2,347	(525)	6,612	(1,461)
Net change in unrealized gain (loss) on private company investments	0	(155)	19	(155)
Other-than-temporary impairment loss	0	0	(75)	0
Interest expense not allocated to segments	(2,339)	(1,844)	(4,441)	(3,561)
Other income and expenses not allocated to segments, net	(2,597)	(3,213)	(4,361)	(5,625)
Amortization of intangible assets	(676)	(254)	(1,197)	(509)
Gain (loss) on change in fair value of debt	918	(142)	1,494	(1,061)
Gain on disposal of subsidiary	0	17	0	17
Equity in net income (loss) of investee	201	(385)	168	(284)
(Loss) income from continuing operations before income tax expense (benefit)	(228)	(4,072)	2,248	(6,422)
Income tax (benefit) expense	168	190	(545)	444
(Loss) income from continuing operations	(396)	(4,262)	2,793	(6,866)
Operating Segments
Segment Reporting Information [Line Items]
Total segment operating income	1,788	1,708	2,807	3,428
Extended Warranty | Operating Segments
Segment Reporting Information [Line Items]
Total segment operating income	1,035	1,090	1,602	1,936
Leased Real Estate | Operating Segments
Segment Reporting Information [Line Items]
Total segment operating income	$ 753	$ 618	$ 1,205	$ 1,492