v2.3.0.15
Condensed Consolidated Balance Sheets (Parenthetical)
Sep. 30, 2011
Dec. 31, 2010
Sep. 30, 2011
Class A ordinary shares, U.S. [Member]
USD ($)
Dec. 31, 2010
Class A ordinary shares, U.S. [Member]
USD ($)
Sep. 30, 2011
Common Class B, Par Value In GBP [Member]
GBP (£)
Dec. 31, 2010
Common Class B, Par Value In GBP [Member]
GBP (£)
Common shares, par value  $ 0.1$ 0.1£ 1£ 1
Common shares, shares authorized  450,000,000450,000,00050,00050,000
Common shares, shares issued  235,800,000150,000,00050,00050,000
Treasury shares, shares held5,300,0007,100,000