Calculation of Basic and Diluted Earnings Per Share (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Basic earnings per share
Net income attributable to Albemarle Corporation	$ 99,261	$ 116,098	$ 245,036	$ 336,837
Weighted-average common shares for basic earnings per share	89,327	89,935	89,246	91,094
Basic earnings per share	$ 1.11	$ 1.29	$ 2.75	$ 3.70
Diluted earnings per share
Net income attributable to Albemarle Corporation	$ 99,261	$ 116,098	$ 245,036	$ 336,837
Weighted-average common shares for basic earnings per share	89,327	89,935	89,246	91,094
Incremental shares under stock compensation plans	552	1,023	713	996
Total shares	89,879	90,958	89,959	92,090
Diluted earnings per share	$ 1.10	$ 1.28	$ 2.72	$ 3.66