Intangible Assets

12 Months Ended

Dec. 31, 2015

Goodwill And Intangible Assets Disclosure [Abstract]

Intangible Assets

6. Intangible Assets

The following table presents intangible assets as of December 31:

	2015						2014
	Gross Carrying Amount			Accumulated Amortization			Gross Carrying Amount		Accumulated Amortization
	(In thousands)
Customer relationships	$	148,910		$	(12,968	)	$	18,423	$	(2,695	)
Non-compete agreements		766			(170	)		392		(31	)
Trade names		51,361			(4,155	)		1,234		(95	)
Favorable lease intangibles		6,408			(548	)		—		—
Total intangible assets	$	207,445		$	(17,841	)	$	20,049	$	(2,821	)
Unfavorable lease obligations (included in Accrued liabilities and Other long-term liabilities)	$	(19,547	)	$	2,072		$	—	$	—

In connection with the acquisition of ProBuild, we recorded intangible assets of $184.5 million, which includes $50.1 million of trade names, $128.0 million of customer relationships and $6.4 million of favorable lease intangibles. We also recorded $19.5 million of unfavorable lease obligations. The weighted average useful lives of the acquired assets are 9.7 years for trade names, 13.5 years for customer relationships, and 10.0 years for both the favorable and unfavorable lease intangibles.

During the years ended December 31, 2015, 2014, and 2013, we recorded amortization expense in relation to the above-listed intangible assets of $11.9 million, $1.1 million, and $0.4 million, respectively.  In addition, as a result of the facility closure activities following the ProBuild acquisition, we recorded a $1.4 million impairment charge against our intangible assets during 2015. We recognized this impairment charge in selling, general, and administrative expense in the accompanying consolidated statement of operations and comprehensive income (loss).   The following table presents the estimated amortization expense for these intangible assets for the years ending December 31 (in thousands):

2016	$	22,495
2017		20,652
2018		19,504
2019		18,457
2020		15,274
Thereafter		75,747
Total future net intangible amortization expense	$	172,129