The Company has various operating leases primarily for equipment, delivery centers and office space, which generally contain renewal options. Rent expense under operating leases was approximately $30.0 million, $30.2 million and $29.7 million for the years ended December 31, 2011, 2010 and 2009, respectively.

In 2008, the Company sub-leased one of its delivery centers to a third party for the remaining term of the original lease. The sub-lease began on January 1, 2009 and rental income received over the term of the lease will be recognized on a straight-line basis. Future minimum sub-lease rental receipts are shown in the table below.

The future minimum rental payments and receipts required under non-cancelable operating leases as of December 31, 2011 are as follows (amounts in thousands):

			Operating Leases		Sub-Lease Income
2012		$	24,731	$	1,823
2013			20,897		1,823
2014			14,339		1,823
2015			6,473		2,234
2016			4,059		2,234
Thereafter			5,729		9,849
	Total	$	76,228	$	19,786

In addition, the Company records operating lease expense on a straight-line basis over the life of the lease as described in Note 1. The deferred lease liability as of December 31, 2011 and 2010 was $6.7 million and $10.4 million, respectively.

The future minimum rental payments for capital leases as of December 31, 2011 are as follows (amounts in thousands) and the current portion and the long-term portion of the obligation are included in the Other current liabilities in the accompanying Consolidated Balance Sheets:

			Capital Leases
Future rental payments		$	366
Less amount representing interest			(11)
	Present value of minimum lease payments		355
Less current portion			(355)
	Long-term portion	$	-

The Company has two delivery centers classified as capital leases at December 31, 2011. The amounts applicable to these leases included in property, plant and equipment are as follows (amounts in thousands):

		December 31,
	2011		2010
Historical cost	$	12,181	$	12,181
Less: Accumulated depreciation		(12,181)		(11,871)
	$	-	$	310

The Company records asset retirement obligations for its delivery center leases. Capitalized costs related to asset retirement obligations are included in Other long-term assets in the accompanying Consolidated Balance Sheets while the asset retirement obligation (“ARO”) liability is included in Other long-term liabilities in the accompanying Consolidated Balance Sheets. Following is a summary of the amounts recorded (amounts in thousands):

		Balance at December 31, 2010		Additions and Modifications		Accretion		Settlements		Balance at December 31, 2011

ARO liability at inception	$	1,645	$	278	$	-	$	(512)	$	1,411
Accumulated accretion		655		9		23		(16)		671
	$	2,300	$	287	$	23	$	(528)	$	2,082

		Balance at December 31, 2009		Additions and Modifications		Accretion		Settlements		Balance at December 31, 2010

ARO liability at inception	$	1,798	$	406	$	-	$	(559)	$	1,645
Accumulated accretion		805		-		82		(232)		655
	$	2,603	$	406	$	82	$	(791)	$	2,300

Increases to ARO result from a new lease agreement or modifications on an ARO from a preexisting lease agreement. Modifications to ARO liabilities and accumulated accretion occur when lease agreements are amended or when assumptions change, such as the rate of inflation. Modifications are accounted for prospectively as changes in estimates. Settlements occur when leased premises are vacated and the actual cost of restoration is paid. Differences between the actual costs of restoration and the balance recorded as ARO liabilities are recognized as gains or losses in the accompanying Consolidated Statements of Operations and Comprehensive Income.