Other Income (Expense) - Other income (expense) summary (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Investment income, net
Interest and dividend income	$ 252	$ 2,130	$ 442	$ 4,389
Accretion income	579	640	1,041	1,262
Total net investment income from available-for-sale securities	831	2,770	1,483	5,651
Interest income from investments in special purpose entities	2,050	2,003	4,101	4,005
Interest accrued on notes receivable and other interest	78	665	105	995
Total investment income, net	2,959	5,438	5,689	10,651
Interest expense
Interest expense and amortization of discount and issuance costs for Senior Notes issued by special purpose entity	(2,191)	(2,189)	(4,382)	(4,377)
Interest expense	(954)	(456)	(1,798)	(1,145)
Total interest expense	(3,145)	(2,645)	(6,180)	(5,522)
Claim settlement	0	0	12,548	0
Other, net
Fees and expenses for the SEC investigation	0	(7,430)	0	(7,430)
Accretion income from retained interest investments	243	227	484	438
Hunting lease income	169	169	370	378
Other income, net	189	21	196	178
Other, net	601	(7,013)	1,050	(6,436)
Total other income (expense)	$ 415	$ (4,220)	$ 13,107	$ (1,307)