Equity Investees (Details)	Dec. 31, 2011
Ashapura Volclay Limited [Member]
Equity method investments in and advances to affiliates and joint ventures
Ownership interest (in hundredths)	50.00%
CETCO-Bentonit Uniao Technologias Ambientais Ltda. [Member]
Equity method investments in and advances to affiliates and joint ventures
Ownership interest (in hundredths)	50.00%
Egypt Mining & Drilling Co. and Egypt Bentonite & Derivatives Co. [Member]
Equity method investments in and advances to affiliates and joint ventures
Ownership interest (in hundredths)	31.00%
Egypt Nano Technologies Co. [Member]
Equity method investments in and advances to affiliates and joint ventures
Ownership interest (in hundredths)	27.00%
Maprid Tech Cast, S.A. de C.V. [Member]
Equity method investments in and advances to affiliates and joint ventures
Ownership interest (in hundredths)	49.00%
Volclay de Mexico, S.A. de C.V. [Member]
Equity method investments in and advances to affiliates and joint ventures
Ownership interest (in hundredths)	49.00%
Volclay Japan Co., Ltd. [Member]
Equity method investments in and advances to affiliates and joint ventures
Ownership interest (in hundredths)	50.00%