Goodwill and Intangible Assets (Tables)

6 Months Ended

Jun. 30, 2013

Goodwill and Intangible Assets Disclosure [Abstract]

Changes in the carrying amount of goodwill

Changes in the carrying amount of goodwill are as follows:

Balance at January 1, 2012	$	56,493
Goodwill acquired during the period	—
Impairment charges	—
Adjustments to goodwill during the period	—
Balance at December 31, 2012	56,493
Goodwill acquired during the period	—
Impairment charges	—
Adjustments to goodwill during the period	—
Balance at June 30, 2013	$	56,493
Gross goodwill	$	230,737
Accumulated impairment charges	(174,244		)
Balance at June 30, 2013	$	56,493

Summary of intangible assets

Intangible assets consisted of the following:

	December 31, 2012							June 30, 2013
	Gross Carrying Amount		Accumulated Amortization			Intangible Assets, net		Gross Carrying Amount		Accumulated Amortization			Intangible Assets, net
Amortizing intangible assets:
Customer contracts	$	152,629	$	(68,380	)	$	84,249	$	148,992	$	(73,833	)	$	75,159
Other	25,743		(16,488		)	9,255		24,513		(17,740		)	6,773
Total amortizing intangible assets	$	178,372	$	(84,868	)	$	93,504	$	173,505	$	(91,573	)	$	81,932
Intangible assets not subject to amortization						33,427							33,427
Total other intangible assets						$	126,931						$	115,359

Estimated annual amortization expense

Estimated annual amortization expense for each of the fiscal years ending December 31, is presented below:

2013	$	11,174
2014	8,770
2015	8,030
2016	7,028
2017	6,496
2018	6,071