Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Net income	$ 4,087	$ 6,431	$ 9,596	$ 4,345
Other comprehensive income (loss):
Foreign currency translation adjustment	2,138	1,542	(1,662)	638
Reclassification of loss on cash flow hedges, net of tax	0	(956)	143	(956)
Adjustment to retirement benefit liability, net of tax	2	2	4	4
Adjustment to post-retirement health care liability, net of tax	37	18	74	37
Other comprehensive income (loss)	2,177	606	(1,441)	(277)
Total comprehensive income	$ 6,264	$ 7,037	$ 8,155	$ 4,068