Schedule of changes in the benefit obligation, plan assets and funded status of the plan (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Change in benefit obligation:
Benefit obligation at beginning of year	$ 27,927	$ 24,189	$ 20,074
Service cost	0	0	0
Interest cost	1,200	1,154	1,062
Plan participants’ contributions	0	0	0
Net transfer in	0	0	0
Actuarial (gain)/loss	(4,093)	1,869	4,259
Benefits paid	(573)	(560)	(839)
Curtailment gain	0	0	0
Settlement	0	0	0
Foreign currency translation	307	1,275	(367)
Benefit obligation at end of year	24,768	27,927	24,189
Change in plan assets:
Fair value of plan assets at beginning of year	19,652	15,547	14,457
Actual return on plan assets	1,665	1,958	347
Employer contributions	1,880	1,854	1,770
Plan participants’ contributions	0	0	0
Net transfer in	0	0	0
Benefits paid	(573)	(560)	(839)
Settlement	0	0	0
Foreign currency translation	538	853	(188)
Fair value of plan assets at end of year	23,162	19,652	15,547
Funded status at end of year	(1,606)	(8,275)	(8,642)
Net actuarial (gain)/loss recognized in other comprehensive loss	$ (5,763)	$ (141)	$ 4,310