Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2011

Commitments and Contingencies [Abstract]

Schedule of rent expense associated with operating leases

The table below presents rent expenses associated with operating leases for the past three years (in thousands):

	2011		2010		2009
$	62,099	$	64,995	$	67,898

Future minimum lease payments related to non-cancelable operating leases

The table below sets forth the approximate future minimum lease payments as of December 31, 2011 related to non-cancelable operating leases and the non-cancelable portion of certain vehicle operating leases with initial terms of one year or more (in thousands):

2012	41,952
2013	33,801
2014	26,387
2015	19,582
2016	13,682
Thereafter	14,253