Schedule IV (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Supplemental Schedule of Reinsurance Premiums for Insurance Companies [Abstract]
Direct Premiums Written	$ 708,252	$ 548,916	$ 417,769
Ceded Premiums Written	262,340	183,808	144,404
Assumed Premiums Written	(96)	20,820	18,984
Premiums Written, Net	$ 445,816	$ 385,928	$ 292,349
premiums assumed as percentage of net premiums	0.00%	5.40%	6.50%