Income taxes (Tables)

9 Months Ended

Sep. 30, 2015

Income Tax Disclosure [Abstract]

Income (Loss) before Income Taxes

	Three Months Ended				Nine Months Ended
	September 30,				September 30,
(in thousands)	2015		2014		2015		2014
Provision for income taxes	$	(1,157)	$	(902)	$	(2,698)	$	(1,761)