Pension And Severance Benefits (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract]
Service cost	$ 1,864	$ 1,808
Interest on projected benefit obligation	1,297	1,291
Expected return on plan assets	(332)	(429)
Recognized actuarial loss	306	217
Amortization of prior service cost	32	48
Defined benefit and severance plan expense	$ 3,167	$ 2,935