10. Goodwill

Goodwill is assigned to reporting units based upon the specific region where the assets are acquired and associated goodwill resided.

The following table reflects the changes in the carrying amounts of goodwill by reportable segment for the six months ended June 30, 2013 (unaudited):

	Region One		Region Two		Region Three			Region Four		Region Five		Total
Balance as of December 31, 2012	$	193,758	$	32,245	$	66,181		$	62,621	$	84,681	$	439,486
Contingent payments related to acquisitions	—				—			—		—		—
Foreign currency translation					(191		)					(191		)
Balance as of June 30, 2013	$	193,758	$	32,245	$	65,990		$	62,621	$	84,681	$	439,295