Other Income (Expense) - Components (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Investment income, net
Interest and dividend income	$ 1,813	$ 2,880
Accretion income	61	221
Net realized loss on the sale of investments	(2)	(1,078)
Other-than-temporary impairment loss		(63)
Unrealized gain (loss) on investments, net	2,049	(538)
Interest income from investments in SPEs	2,049	2,050
Interest accrued on notes receivable and other interest	76	193
Total investment income, net	6,046	3,665
Interest expense
Interest expense and amortization of discount and issuance costs for Senior Notes issued by SPE	(2,199)	(2,196)
Other interest expense	(743)	(829)
Total interest expense	(2,942)	(3,025)
Other income (expense), net
Gain on land contribution	1,472
Accretion income from retained interest investments	320	290
Insurance proceeds	279
Hurricane expense	(322)
Miscellaneous expense, net	(51)	(13)
Other income, net	1,698	277
Total other income, net	$ 4,802	$ 917