XML 26 R18.htm IDEA: XBRL DOCUMENT  v2.3.0.11
Comprehensive Income
6 Months Ended
Jun. 30, 2011
Comprehensive Income [Abstract]  
Comprehensive Income
11.
Comprehensive Income

The components of total comprehensive income are shown below:

   
Three Months Ended June 30,
  
Six Months Ended June 30,
 
(Thousands of Dollars)
 
2011
  
2010
  
2011
  
2010
 
Net income
 $24,672  $24,396  $34,910  $32,095 
Other comprehensive income:
                
After-tax net realized losses on derivative transactions reclassified into earnings
  43   42   86   85 
Comprehensive income
 $24,715  $24,438  $34,996  $32,180