Other Income (Expense) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Investment income, net
Interest and dividend income	$ 4,024	$ 252	$ 8,573	$ 442
Accretion income	399	579	1,320	1,041
Realized gain on the sale of investments	7,739	0	10,861	0
Other-than-temporary impairment loss	0	0	(366)	0
Total net investment income from available-for-sale securities	12,162	831	20,388	1,483
Interest income from investments in SPEs	2,050	2,050	4,101	4,101
Interest accrued on notes receivable and other interest	91	78	169	105
Total investment income, net	14,303	2,959	24,658	5,689
Interest expense
Interest expense and amortization of discount and issuance costs for Senior Notes issued by SPE	(2,194)	(2,191)	(4,387)	(4,382)
Other interest expense	(841)	(954)	(1,691)	(1,798)
Total interest expense	(3,035)	(3,145)	(6,078)	(6,180)
Claim settlement	0	0	0	12,548
Other income, net
Accretion income from retained interest investments	271	243	534	484
Hunting lease income	140	138	279	277
Miscellaneous income, net	181	220	3,830	289
Other income, net	592	601	4,643	1,050
Total other income, net	$ 11,860	$ 415	$ 23,223	$ 13,107