Goodwill
9 Months Ended
Sep. 30, 2012
Goodwill [Abstract]  
Goodwill
Goodwill
     
The following table presents the changes in the Company’s goodwill balance:

Balance at December 31, 2010
$
224,920

Goodwill arising from acquisitions
31,140

Balance at December 31, 2011
256,060

Other
(23
)
Balance at September 30, 2012
$
256,037


 
Goodwill in 2011 arose from four acquisitions completed in that year. The movement in 2012 relates to revisions to the preliminary purchase price allocation in respect of acquisitions in the second half of 2011. There were no business acquisitions during the nine months ended September 30, 2012.
        
The Company's most recent annual impairment analysis was performed in the fourth quarter of the year ended December 31, 2011 and indicated that the fair value of each of its three reporting units significantly exceeded the carrying amount of the respective reporting unit's book value of goodwill at that time.