Goodwill and Other Intangible Assets (Tables)

6 Months Ended

Jun. 30, 2012

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill

	Animal Hospital			Laboratory		All Other			Total
Balance as of December 31, 2011	$	1,035,401		$	96,810	$	105,396		$	1,237,607
Goodwill acquired	102,819			8		10,569			113,396
Other (1)	(5,104		)	2		(372		)	(5,474		)
Balance as of June 30, 2012 (2)	$	1,133,116		$	96,820	$	115,593		$	1,345,529

 ____________________________

⁽¹⁾  Other includes acquisition-price adjustments, which consist primarily of an adjustment related to capital leases, buy- outs and foreign currency translation adjustments.

⁽²⁾  Net of accumulated impairment losses of $21.3 million recorded in 2011, all related to our medical technology business, included in "All Other" in the above table.

Other Intangible Assets

	As of June 30, 2012							As of December 31, 2011
	Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount		Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount
Noncontractual customer relationships	$	101,683	$	(28,103	)	$	73,580	$	82,891	$	(21,147	)	$	61,744
Covenants not-to-compete	12,859		(7,020		)	5,839		13,035		(8,067		)	4,968
Favorable lease assets	7,163		(3,568		)	3,595		5,571		(3,210		)	2,361
Trademarks	7,898		(1,995		)	5,903		7,405		(1,686		)	5,719
Contracts	4,062		(437		)	3,625		3,500		(185		)	3,315
Technology	19,183		(3,832		)	15,351		16,589		(2,342		)	14,247
Client lists	84		(50		)	34		84		(35		)	49
Total	$	152,932	$	(45,005	)	$	107,927	$	129,075	$	(36,672	)	$	92,403

Aggregate amortization expense

	Three Months Ended June 30,				Six Months Ended June 30,
	2012		2011		2012		2011
Aggregate amortization expense	$	5,342	$	2,604	$	10,218	$	5,259

Estimated amortization expense related to intangible assets

Remainder of 2012	$	10,748
2013	19,710
2014	17,298
2015	15,429
2016	12,201
Thereafter	32,541
Total	$	107,927