Business Segment and Geographic Information (Reconciliation to Consolidated Statements of Income (Loss)) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 31, 2010	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Segment Reporting [Abstract]
Operating Income (Loss)		$ 25,664	$ 53,482	$ 31,575
Income (Loss) from Equity Method Investments	100	4,743	5,451	8,658
Other Nonoperating Income (Expense)		(208)	1,942	1,364
Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net		3,245	196	553
Interest Income (Expense), Nonoperating, Net		(4,304)	(4,911)	184
Business Combination, Bargain Purchase, Gain Recognized, Amount		0	0	3,173
Income (loss) before income tax expense (benefit)		$ 22,650	$ 55,768	$ 44,401