Consolidated Statements of Stockholders' Equity - USD ($) shares in Thousands	Total	Accumulated deficit [Member]	Accumulated other comprehensive income (loss) [Member]	Treasury Stock [Member]	Common Class A [Member]	Common Class A [Member] Common Stock [Member]	Common Class B [Member]	Common Class B [Member] Common Stock [Member]
Balance at Dec. 31, 2015	$ 246,926,000	$ (18,217,000)	$ 13,587,000	$ (11,011,000)		$ 259,383,000		$ 3,184,000
Net income (loss)	1,969,000	1,969,000	0	0		0		0
Unrealized investment gains (losses), net	205,000	0	205,000	0		0		0
Total comprehensive loss	2,174,000	1,969,000	205,000	0		0		0
Stock-based compensation	0
Balance at Dec. 31, 2016	249,100,000	(16,248,000)	13,792,000	$ (11,011,000)		259,383,000		3,184,000
Balance, shares at Dec. 31, 2016				(3,136)	52,216		1,002
Net income (loss)	(38,127,000)	(38,127,000)	0	$ 0		0		0
Unrealized investment gains (losses), net	12,540,000	0	12,540,000	0		0		0
Total comprehensive loss	(25,587,000)	(38,127,000)	12,540,000	0		0		0
Stock-based compensation	0
Balance at Dec. 31, 2017	223,513,000	(54,375,000)	26,332,000	$ (11,011,000)		259,383,000		3,184,000
Balance, shares at Dec. 31, 2017				(3,136)	52,216		1,002
Net income (loss)	(11,062,000)	(11,062,000)	0	$ 0		0		0
Unrealized investment gains (losses), net	(25,128,000)	0		0		0		0
Other Comprehensive Income (Loss), Securities, After Tax, Excluding transfers from HTM to AFS	(28,498,000)		(28,498,000)
Unrealized gain from held-to-maturity securities transferred to available-for-sale, net	3,370,000	0	3,370,000	0		0		0
Total comprehensive loss	(36,190,000)	(11,062,000)	(25,128,000)	0		0		0
Stock-based compensation	410,000	0	0	0		410,000		0
Balance at Dec. 31, 2018	187,733,000	(69,599,000)	5,366,000	$ (11,011,000)		259,793,000		3,184,000
Balance, shares at Dec. 31, 2018				(3,136)	52,216		1,002
Accounting standards adopted January 1, 2018	0	(4,162,000)	4,162,000	$ 0		0		0
Stockholders' Equity, adjusted balance	$ 223,513,000	$ (58,537,000)	$ 30,494,000	$ (11,011,000)		$ 259,383,000		$ 3,184,000