9. 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	$	191,941		$	31,840		$	65,770		$	62,052		$	83,519		$	435,122
Contingent payments related to acquisitions	—						—			—			—			—
Adjustment to purchase price allocation (1)	(312		)	(103		)	(111		)	(145		)	(295		)	(966		)
Foreign currency translation							(279		)							(279		)
Balance as of June 30, 2013	$	191,629		$	31,737		$	65,380		$	61,907		$	83,224		$	433,877

(1) Primarily related to fair value adjustments on accounts receivable.