Pensions (Details) - Defined benefit pension plans - USD ($) $ in Thousands	5 Months Ended	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2016
Change in projected benefit obligation and plan assets
Projected benefit obligation, beginning balance	$ 686	$ 782
Service cost	122	256
Interest cost	6	22
Net periodic pension expense	128	289
Net actuarial loss (gain)	(32)	94
Benefits paid	0	0
Cumulative translation adjustment		(38)
Projected benefit obligation, ending balance	782	1,116
Fair value of plan assets	(48)	(184)
Unfunded pension liability	$ 734	$ 932