Deferred policy acquisition costs (Tables)

12 Months Ended

Dec. 31, 2017

Deferred Policy Acquisition Costs Disclosures [Abstract]

Deferred Policy Acquisition Costs

The following table presents the amounts of policy acquisition costs deferred and amortized for the years ended:

	Year Ended December 31,
	2017			2016			2015
	(in thousands)
Balance, beginning of year	$	10,150		$	(1,696	)	$	(3,763	)
Policy acquisition costs deferred:
Direct commissions	32,927			28,027			26,142
Ceding commissions	(9,984		)	(9,213		)	(34,478		)
Other underwriting and policy acquisition costs	2,827			2,999			3,013
Policy acquisition costs deferred	25,770			21,813			(5,323		)
Amortization of net policy acquisition costs	(24,145		)	(9,967		)	7,390
Balance, end of year	$	11,775		$	10,150		$	(1,696	)