Goodwill and Other Long-Lived Assets (Tables)

6 Months Ended

Jun. 30, 2017

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill

The following table presents the changes in the carrying amount of our goodwill for the six months ended June 30, 2017 (in thousands):

	Animal Hospital			Laboratory		All Other			Total
Balance as of December 31, 2016
Goodwill	$	2,047,894		$	101,283	$	145,302		$	2,294,479
Accumulated impairment losses	—			—		(130,057		)	(130,057		)
Subtotal	2,047,894			101,283		15,245			2,164,422
Goodwill acquired	109,090			—		—			109,090
Foreign translation adjustment	6,301			16		—			6,317
Other (1)	(15,564		)	—		—			(15,564		)
Balance as of June 30, 2017
Goodwill	2,147,721			101,299		145,302			2,394,322
Accumulated impairment losses	—			—		(130,057		)	(130,057		)
Subtotal	$	2,147,721		$	101,299	$	15,245		$	2,264,265

 ____________________________

⁽¹⁾  "Other" consists primarily of measurement period adjustments and the sale of an animal hospital.

Summary of Other Intangible Assets

Our acquisition related amortizable intangible assets as of June 30, 2017 and December 31, 2016 are as follows (in thousands):

	As of June 30, 2017							As of December 31, 2016
	Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount		Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount
Non-contractual customer relationships	$	232,789	$	(78,875	)	$	153,914	$	218,847	$	(62,331	)	$	156,516
Covenants not-to-compete	26,276		(9,847		)	16,429		23,990		(7,580		)	16,410
Favorable lease assets	6,509		(3,112		)	3,397		9,451		(5,855		)	3,596
Technology	1,377		(893		)	484		1,377		(795		)	582
Trademarks	30,752		(10,291		)	20,461		30,144		(7,713		)	22,431
Client lists	10		(2		)	8		10		(1		)	9
Franchise rights	11,730		(3,324		)	8,406		11,730		(2,737		)	8,993
Total	$	309,443	$	(106,344	)	$	203,099	$	295,549	$	(87,012	)	$	208,537

Estimated Amortization Expense Related to Intangible Assets

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

	Three Months Ended June 30,				Six Months Ended June 30,
	2017		2016		2017		2016
Aggregate amortization expense	$	11,338	$	9,798	$	22,763	$	16,026

Estimated Amortization Expense Related to Indefinite Intangible Assets

The estimated amortization expense related to other intangible assets for the remainder of 2017 and each of the succeeding years thereafter, as of June 30, 2017, is as follows (in thousands):

Definite-lived intangible assets:
Remainder of 2017	$	22,782
2018	43,018
2019	39,864
2020	34,819
2021	24,485
Thereafter	38,131
Total	$	203,099
Indefinite-lived intangible assets:
Trademarks	4,059
Total intangible assets	$	207,158