Schedule V - Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Allowance for Premiums Receivable [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of period	$ 1,977	$ 2,088	$ 595
Additions amounts charged to expense	488	276	1,493
Deductions amounts written off or disposals	(353)	(387)	0
Balance at end of period	2,112	1,977	2,088
Valuation Allowance for Deferred Tax Assets [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of period	623	529	489
Additions amounts charged to expense	68	94	40
Deductions amounts written off or disposals	0	0	0
Balance at end of period	$ 691	$ 623	$ 529