Consolidated Statements of Comprehensive Income (unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Net income	$ 19,667	$ 2,274	$ 20,649	$ 13,442
Other comprehensive income/(loss):
Foreign currency translation adjustments	885	952	562	(2,884)
Comprehensive income	20,736	3,597	21,567	11,217
Interest Rate Swap Agreement [Member]
Other comprehensive income/(loss):
Interest rate swap agreement, net of tax of $21, $74, $35 and $105 at respective dates	39	139	66	195
Pension Plan [Member]
Other comprehensive income/(loss):
Pension plan amortization of net actuarial loss and prior service cost, net of tax of $70, $115, $140 and $231 at respective dates	$ 145	$ 232	$ 290	$ 464