Pension And Severance Benefits (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract]
Service cost	$ 1,765	$ 1,690	$ 3,573	$ 3,379
Interest on projected benefit obligation	1,208	1,350	2,499	2,695
Expected return on plan assets	(326)	(401)	(755)	(801)
Recognized actuarial loss	250	200	467	399
Amortization of prior service cost	16	32	64	64
Defined benefit and severance plan expense	$ 2,913	$ 2,871	$ 5,848	$ 5,736