XML 29 R22.htm IDEA: XBRL DOCUMENT v2.4.0.6
Income Taxes (Tables)
9 Months Ended
Sep. 30, 2012
Income Taxes [Abstract]  
Reconciliation of Unrecognized Tax Benefits
A reconciliation of the amount of unrecognized tax benefit is as follows:

(Millions of Dollars)
 
Sept. 30, 2012
  
Dec. 31, 2011
 
Unrecognized tax benefit — Permanent tax positions
 $1.4  $0.5 
Unrecognized tax benefit — Temporary tax positions
  8.8   10.9 
Total unrecognized tax benefit
 $10.2  $11.4 
Tax Benefits Associated with NOL and Tax Credit Carryforwards
The unrecognized tax benefit balance was reduced by the tax benefits associated with net operating loss (NOL) and tax credit carryforwards.  The amounts of tax benefits associated with NOL and tax credit carryforwards are as follows:

(Millions of Dollars)
 
Sept. 30, 2012
  
Dec. 31, 2011
 
NOL and tax credit carryforwards
 $(6.1) $(3.7)