Equity Investees (Details Textual) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011		Dec. 31, 2010		Dec. 31, 2009
Schedule of Equity Method Investments [Line Items]
Income (loss) from affiliates and joint ventures	$ 5,235	[1]	$ (10,997)	[1]	$ 6	[1]
Equity Investees (Textual) [Abstract]
Equity method investments			0
Albagle Enterprise Limited [Member]
Schedule of Equity Method Investments [Line Items]
Income (loss) from affiliates and joint ventures			7,196
Ashapura AMCOL N.V. [Member]
Schedule of Equity Method Investments [Line Items]
Income (loss) from affiliates and joint ventures			6,875
Loss from sale of joint venture and affiliated entities	$ 2,104

[1] Restated