Earnings Per Share (Tables)
|9 Months Ended|
Sep. 30, 2011
|Earnings Per Share [Abstract]|
|Common share amounts used to compute earnings per share||
Tabular disclosure of the weighted average number of shares used in calculating basic net earnings per share (or unit) and diluted earnings per share (or unit).
Reference 1: http://www.xbrl.org/2003/role/presentationRef