Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Net income	$ 9,963	$ 7,584	$ 27,770	$ 23,831
Other comprehensive income (loss):
Foreign currency translation adjustment	(664)	(23)	(271)	(9)
Amortization of actuarial loss, net of tax expense of $205, and $151 for the three-month periods ended June 30, 2012, and 2011, respectively; and net of a tax expense of $410 and $303 for the six-month periods ended June 30, 2012, and 2011, respectively.	318	236	640	472
Other comprehensive income (loss):	(346)	213	369	463
Comprehensive income	$ 9,617	$ 7,797	$ 28,139	$ 24,294