Consolidated Statements of Stockholder's Equity Statement - USD ($) $ in Thousands	Total	Accumulated deficit [Member]	Accumulated other comprehensive income [Member]	Treasury stock [Member]	Common Stock Class A [Member] Common stock [Member]	Common Stock Class B [Member] Common stock [Member]
Balance at Dec. 31, 2018	$ 187,733	$ (69,599)	$ 5,366	$ (11,011)	$ 259,793	$ 3,184
Net income (loss)	(3,802)	(3,802)
Unrealized investment gains (losses), net	26,880		26,880
Comprehensive income (loss)	23,078	(3,802)	26,880
Stock-based compensation	1,083				1,083
Balance at Mar. 31, 2019	211,894	(73,401)	32,246	(11,011)	260,876	3,184
Balance at Dec. 31, 2018	187,733	(69,599)	5,366	(11,011)	259,793	3,184
Net income (loss)	(6,321)	(6,321)
Comprehensive income (loss)	72,056
Balance at Sep. 30, 2019	261,342	(75,920)	83,743	(11,011)	261,346	3,184
Balance at Mar. 31, 2019	211,894	(73,401)	32,246	(11,011)	260,876	3,184
Net income (loss)	(4,565)	(4,565)
Unrealized investment gains (losses), net	28,976		28,976
Comprehensive income (loss)	24,411	(4,565)	28,976
Stock-based compensation	127				127
Balance at Jun. 30, 2019	236,432	(77,966)	61,222	(11,011)	261,003	3,184
Net income (loss)	2,046	2,046
Unrealized investment gains (losses), net	22,521		22,521
Comprehensive income (loss)	24,567	2,046	22,521
Stock-based compensation	343				343
Balance at Sep. 30, 2019	261,342	(75,920)	83,743	(11,011)	261,346	3,184
Accounting standards adopted January 1, 2020	(395)	(395)
Balance at Dec. 31, 2019	259,836	(70,969)	77,117	(11,011)	261,515	3,184
Net income (loss)	(3,584)	(3,584)
Unrealized investment gains (losses), net	(40,070)		(40,070)
Comprehensive income (loss)	(43,654)	(3,584)	(40,070)
Stock-based compensation	(53)				(53)
Balance at Mar. 31, 2020	215,734	(74,948)	37,047	(11,011)	261,462	3,184
Balance at Dec. 31, 2019	259,836	(70,969)	77,117	(11,011)	261,515	3,184
Net income (loss)	(12,526)	(12,526)
Comprehensive income (loss)	36,160
Balance at Sep. 30, 2020	296,754	(83,890)	125,804	(11,011)	262,667	3,184
Balance at Mar. 31, 2020	215,734	(74,948)	37,047	(11,011)	261,462	3,184
Net income (loss)	(1,027)	(1,027)
Unrealized investment gains (losses), net	74,647		74,647
Comprehensive income (loss)	73,620	(1,027)	74,647
Stock-based compensation	439				439
Balance at Jun. 30, 2020	289,793	(75,975)	111,694	(11,011)	261,901	3,184
Net income (loss)	(7,915)	(7,915)
Unrealized investment gains (losses), net	14,110		14,110
Comprehensive income (loss)	6,195	(7,915)	14,110
Stock-based compensation	766				766
Balance at Sep. 30, 2020	$ 296,754	$ (83,890)	$ 125,804	$ (11,011)	$ 262,667	$ 3,184

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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