Intangible Assets

6 Months Ended

Jun. 30, 2012

Intangible Assets, Net (Excluding Goodwill) [Abstract]

Intangible Assets

. Intangible Assets

The following table summarizes the components of our intangible assets at the dates indicated:

	June 30, 2012						December 31, 2011
	Gross Carrying Amount		Accumulated Amortization		Carrying Value		Gross Carrying Amount		Accumulated Amortization		Carrying Value
Refinery Services:
Customer relationships	$	94,654	$	65,639	$	29,015	$	94,654	$	62,111	$	32,543
Licensing agreements	38,678		21,184		17,494		38,678		19,476		19,202
Supplier relationships	36,469		35,287		1,182		36,469		34,105		2,364
Segment total	169,801		122,110		47,691		169,801		115,692		54,109
Supply & Logistics:
Customer relationships	35,430		24,994		10,436		35,430		23,584		11,846
Intangibles associated with lease	13,260		2,328		10,932		13,260		2,092		11,168
Trade names	18,888		18,888		—		18,888		17,048		1,840
Segment total	67,578		46,210		21,368		67,578		42,724		24,854
Other	18,332		3,866		14,466		17,292		2,899		14,393
Total	$	255,711	$	172,186	$	83,525	$	254,671	$	161,315	$	93,356

Our amortization expense for the periods presented was as follows:

	Three Months Ended June 30,				Six Months Ended June 30,
	2012		2011		2012		2011
Amortization expense	$	5,355	$	7,473	$	10,870	$	14,646

We estimate that our amortization expense for the next five years will be as follows:

Remainder of 2012	$	9,225
2013	$	14,531
2014	$	12,232
2015	$	10,424
2016	$	8,962