XML 36 R57.htm IDEA: XBRL DOCUMENT v2.4.0.8
Earnings Per Share - Additional Disclosures (Details) (USD $)
In Millions, unless otherwise specified
3 Months Ended 6 Months Ended
Jun. 30, 2013
Feb. 11, 2008
Jun. 30, 2013
Stock Options [Member]
Jun. 30, 2012
Stock Options [Member]
Jun. 30, 2013
Stock Options [Member]
Jun. 30, 2012
Stock Options [Member]
Feb. 15, 2013
2008 Notes [Member]
Dec. 31, 2012
2008 Notes [Member]
Jun. 25, 2012
2008 Notes [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]                  
Common stock included in share lending agreement 3.8 3.8              
Notes repurchased             $ 5.2 $ 50.3 $ 15.0
Anti-dilutive securities excluded from calculation of earnings per share     0.1 0.1 0.1 0.1