Shareholders' Equity - Accumulated Other Comprehensive Loss Schedule of Other Comprehensive Income (Loss) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Before-tax amount
Foreign currency translation adjustments	$ 1,873	$ (5,967)	$ (2,610)
Unrealized gain (loss) on investments	57	(54)	58
Amortization of benefit plan costs	(9,378)	(30,524)	(18,419)
Total other comprehensive income (loss), before tax	(7,448)	(36,545)	(20,971)
Tax (provision) benefit
Foreign currency translation adjustments	0	0	0
Unrealized gain (loss) on investments	(19)	20	(21)
Amortization of benefit plan costs	0	11,165	6,559
Total other comprehensive loss, tax (provision) benefit	(19)	11,185	6,538
After-tax amount
Foreign currency translation adjustments	1,873	(5,967)	(2,610)
Unrealized gain (loss) on investments	38	(34)	37
Pension adjustments	(9,378)	(19,359)	(11,860)
Total other comprehensive loss, net of tax	$ (7,467)	$ (25,360)	$ (14,433)