Goodwill and Other Long-Lived Assets (Tables)

3 Months Ended

Mar. 31, 2016

Goodwill and Intangible Assets Disclosure [Abstract]

The following table presents the changes in the carrying amount of our goodwill for the three months ended March 31, 2016 (in thousands):



	Animal Hospital		Laboratory		All Other			Total
Balance as of December 31, 2015
Goodwill	$	1,402,106	$	101,269	$	144,332		$	1,647,707
Accumulated impairment losses	—		—		(130,057		)	(130,057		)
Subtotal	1,402,106		101,269		14,275			1,517,650
Goodwill acquired	129,246		—		120			129,366
Foreign translation adjustment	9,013		31		—			9,044
Other ⁽¹⁾	329		—		—			329
Balance as of March 31, 2016
Goodwill	1,540,694		101,300		144,452			1,786,446
Accumulated impairment losses	—		—		(130,057		)	(130,057		)
Subtotal	$	1,540,694	$	101,300	$	14,395		$	1,656,389

____________________________


⁽¹⁾	"Other" consists primarily of measurement period adjustments.

Other Intangible Assets

Our acquisition related amortizable intangible assets at March 31, 2016 and December 31, 2015 are as follows (in thousands):



	As of March 31, 2016							As of December 31, 2015
	Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount		Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount
Non-contractual customer relationships	$	132,741	$	(54,491	)	$	78,250	$	116,082	$	(48,821	)	$	67,261
Covenants not-to-compete	16,311		(5,364		)	10,947		12,435		(4,779		)	7,656
Favorable lease assets	9,461		(5,543		)	3,918		9,441		(5,440		)	4,001
Technology	1,377		(643		)	734		1,377		(589		)	788
Trademarks	11,242		(4,535		)	6,707		10,551		(4,086		)	6,465
Franchise rights	11,730		(1,857		)	9,873		11,730		(1,564		)	10,166
Total	$	182,862	$	(72,433	)	$	110,429	$	161,616	$	(65,279	)	$	96,337

Estimated amortization expense related to intangible assets

The following table summarizes our aggregate amortization expense related to acquisition related intangible assets (in thousands):



	Three Months Ended March 31,
	2016		2015
Aggregate amortization expense	$	6,228	$	5,526

The estimated amortization expense related to acquisition related intangible assets for the remainder of 2016 and each of the succeeding years thereafter, as of March 31, 2016, is as follows (in thousands):



Finite-lived intangible assets:
Remainder of 2016	$	20,119
2017	21,442
2018	18,033
2019	15,070
2020	10,234
Thereafter	25,531
Total	$	110,429
Indefinite-lived intangible assets:
Trademarks	4,040
Total intangible assets	$	114,469

Estimated amortization expense related to indefinite intangible assets



Finite-lived intangible assets:
Remainder of 2016	$	20,119
2017	21,442
2018	18,033
2019	15,070
2020	10,234
Thereafter	25,531
Total	$	110,429
Indefinite-lived intangible assets:
Trademarks	4,040
Total intangible assets	$	114,469