Leases

At December 31, 2012, we were obligated under operating leases covering office equipment, office and warehouse space, transponders and transportation equipment expiring at various dates. Future minimum lease payments required under our leasing arrangements at December 31, 2012 are approximately as follows:



	2013		2014		2015		2016		2017		Thereafter
Future minimum lease payments	$	18,600	$	16,300	$	13,800	$	10,700	$	10,200	$	12,500

Total rental expense under these operating leases was approximately $22,000, $20,100 and $21,600 in the years ended December 31, 2012, 2011 and 2010, respectively.

We have entered into several operating lease agreements, some of which contain provisions for future rent increases, rent-free periods, or periods in which rent payments are reduced. The total amount of rental payments due over the lease term is being charged to rent expense on the straight-line method over the term of the lease. The difference between rent expense recorded and the amount paid is credited or charged to deferred rent obligation, which is included in other current liabilities and other long-term liabilities in the accompanying Consolidated Balance Sheets.