REINSURANCE (Reinsurance Recoverables) (Details) - USD ($) $ in Thousands		Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016	Dec. 31, 2015
REINSURANCE [Abstract]
Reinsurance recoverable on paid losses		$ 11,973	$ 7,451
Reinsurance recoverable on unpaid losses	[1]	326,042	41,079	$ 17,057	$ 7,496
Reinsurance recoverable, net		$ 338,015	$ 48,530

[1] Reinsurance recoverable in this table includes only ceded loss and LAE reserves.