Intangible Assets

6 Months Ended

Jun. 30, 2012

Intangible assets consist of intellectual property, non-compete agreements, customer lists and trademarks. Intellectual property, non-compete agreements and trademarks are amortized on a straight-line basis over their estimated useful lives or contract periods, generally ranging from 3 to 20 years. Customer lists are amortized based on the attrition rate of our customers. The amounts were based, in part, on an analysis of the incremental cash flows expected to be derived from the customer lists using historic retention rates and an appropriate discount rate. Amortization expense related to these intangible assets was $5,838 and $11,216 for the three and six months ended June 30, 2012, respectively, and $3,583 and $7,114 for the three and six months ended June 30, 2011, respectively.

Intangible assets subject to amortization at June 30, 2012 and December 31, 2011 consist of the following:


	June 30, 2012							December 31, 2011
	Gross Carrying Amount		Accumulated Amortization		Net		Weighted Average Useful Life (in years)	Gross Carrying Amount		Accumulated Amortization		Net	Weighted Average Useful Life (in years)
Customer lists	$	81,940	$	(23,649)	$	58,291	9.4	$	71,783	$	(17,809)	53,974	9.6
Intellectual property		37,569		(14,076)		23,493	4.0		26,134		(9,316)	16,818	2.2
Non-compete		1,000		(686)		314	0.5		2,007		(1,546)	461	0.7
Trademarks		2,234		(600)		1,634	5.1		2,232		(411)	1,821	5.6
Fully amortized intangibles		5,406		(5,406)		—	—		4,199		(4,199)	—	—
Total	$	128,149	$	(44,417)	$	83,732	7.6	$	106,355	$	(33,281)	73,074	7.4

The estimated amortization expense for intangible assets for the next five years and thereafter is as follows:

The entire disclosure for all or part of the information related to intangible assets.