Consolidated Statements of Stockholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common Class A [Member]	Common Class B [Member]	Accumulated deficit [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Treasury stock [Member]
Balance at Dec. 31, 2012	$ 263,108	$ 259,383	$ 3,184	$ (17,335)	$ 28,887	$ (11,011)
Balance, shares at Dec. 31, 2012		52,216	1,002			(3,136)
Net income (loss)	4,793			4,793
Unrealized investment gains (losses), net	(22,092)				(22,092)
Total comprehensive loss	(17,299)			4,793	(22,092)
Warrants exercised, shares		0	0			0
Balance at Dec. 31, 2013	245,809	$ 259,383	$ 3,184	(12,542)	6,795	$ (11,011)
Balance, shares at Dec. 31, 2013		52,216	1,002			(3,136)
Net income (loss)	(6,505)			(6,505)
Unrealized investment gains (losses), net	19,055				19,055
Total comprehensive loss	12,550			(6,505)	19,055
Warrants exercised, shares		0	0			0
Balance at Dec. 31, 2014	258,359	$ 259,383	$ 3,184	(19,047)	25,850	$ (11,011)
Balance, shares at Dec. 31, 2014		52,216	1,002			(3,136)
Net income (loss)	(3,579)			(3,579)
Unrealized investment gains (losses), net	(12,263)				(12,263)
Total comprehensive loss	(15,842)			(3,579)	(12,263)
Warrants exercised, shares		0	0			0
Balance at Dec. 31, 2015	$ 242,517	$ 259,383	$ 3,184	$ (22,626)	$ 13,587	$ (11,011)
Balance, shares at Dec. 31, 2015		52,216	1,002			(3,136)