LIABILITY FOR LOSSES AND SETTELEMT EXPENSES (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Reconciliation of beginning and ending reserves for losses and settlement expenses [Roll Forward]
Gross reserves at beginning of year	$ 732,612	$ 690,532
Re-valuation due to foreign currency exchange rates	525	(1,913)
Less ceded reserves at beginning of year	30,923	20,664
Net reserves at beginning of year	701,164	671,781
Incurred losses and settlement expenses related to:
Current year	352,992	340,706
Prior years	(11,996)	(17,617)
Total incurred losses and settlement expenses	340,996	323,089
Paid losses and settlement expenses related to:
Current year	119,399	120,053
Prior years	193,673	173,986
Total paid losses and settlement expenses	313,072	294,039
Net reserves at end of period	729,088	700,831
Plus ceded reserves at end of period	32,661	25,348
Re-valuation due to foreign currency exchange rates	(168)	282
Gross reserves at end of period	761,581	726,461
Property and casualty insurance [Member]
Incurred losses and settlement expenses related to:
Prior years	$ (12,500)	$ (15,600)
Percentage change in loss and settlement expense reserves for prior accident years (in hundredths)	(2.50%)	(3.20%)
Reinsurance [Member]
Incurred losses and settlement expenses related to:
Prior years	$ 493	$ (2,100)
Percentage change in loss and settlement expense reserves for prior accident years (in hundredths)	0.20%	(1.00%)