Annual report pursuant to Section 13 and 15(d)

Earnings Per Share (Narrative) (Details)

v2.4.0.6
Earnings Per Share (Narrative) (Details)
12 Months Ended
Dec. 31, 2011
Dec. 31, 2010
Dec. 31, 2009
Stock Options And Service-Based Restricted Stock Units [Member]
     
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]      
Antidilutive securities excluded from computation of earnings per share, number of shares 452,907 480,707 1,562,064
Performance-Based Restricted Stock Units [Member]
     
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]      
Antidilutive securities excluded from computation of earnings per share, number of shares 34,448 43,323 44,043