INVESTMENT IN RELATED PARTY INVESTMENT FUND Summarized Income Statements of SILP (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Expenses
Management fee	$ (703)	$ (1,981)	$ (1,325)	$ (9,888)
Interest	(1,579)	(1,578)	(4,702)	(4,684)
Realized and change in unrealized gains (losses)
Net income (loss)	2,183	5,140	(38,150)	26,360
GLRE Limited Partners’ share of net income (loss)	6,431	6,609	(34,086)	51,770
Management fees	703	652	1,981	4,234
Performance allocation	0	673	0	5,654
Solasglas Investment LP (SILP)
Investment income
Dividend income (net of withholding taxes)	170	652	1,204	2,334
Interest income	36	279	262	1,869
Total Investment income	206	931	1,466	4,203
Expenses
Management fee	(703)	(653)	(1,981)	(4,235)
Interest	(176)	(89)	(518)	(2,308)
Dividends	(213)	(96)	(612)	(1,532)
Professional fees and other	(432)	(204)	(764)	(1,009)
Total expenses	(1,524)	(1,042)	(3,875)	(9,084)
Net investment income (loss)	(1,318)	(111)	(2,409)	(4,881)
Realized and change in unrealized gains (losses)
Net realized gain (loss)	(1,412)	14,760	(44,972)	26,989
Net change in unrealized appreciation (depreciation)	10,832	(5,675)	5,811	45,708
Net gain (loss) on investment transactions	9,420	9,085	(39,161)	72,697
Net income (loss)	8,102	8,974	(41,570)	67,816
GLRE Limited Partners’ share of net income (loss)	$ 6,431	$ 6,609	$ (34,086)	$ 51,770