Commitments and Contingencies Purchase Commitments We enter into purchase commitments in the ordinary course of business. As of December 31, 2012 and 2011 , we had $1.2 million in purchase obligations primarily related to delivery equipment. Operating Leases We lease most of our sales and warehouse facilities and a significant number of trucks, vans and certain equipment under operating lease agreements expiring at various dates through 2027, excluding renewal options. Rent expense is recorded on a straight-line basis over the term of the lease, including available renewal option terms, if it is reasonably assured that the renewal options will be exercised. The operating leases generally require us to pay taxes, maintenance and insurance. In most instances, we expect the operating leases that expire will be renewed or replaced in the normal course of business. Future minimum rental payments under non-cancelable operating leases (with initial or remaining lease terms in excess of one year and excluding contracted vehicle maintenance costs) were as follows as of December 31, 2012 (in millions): Year ending December 31, 2013 $ 35.1 2014 29.5 2015 26.0 2016 23.8 2017 21.1 2018 and Thereafter 81.3 Total $ 216.8 For 2012 , 2011 and 2010 , rental expenses for operating and month-to-month leases, including contracted vehicle maintenance costs, were $41.8 million , $38.7 million and $35.8 million , respectively. Capital Leases As of December 31, 2012 and 2011 , we had approximately $12.3 million and $1.3 million , respectively, in capital lease obligations, related to a warehouse facility, refrigeration and other office and warehouse equipment with lease agreements expiring at various dates through 2022, excluding renewal options. Capital lease obligations increased in 2012 compared with 2011 due primarily to the execution of a $10.9 million warehouse facility lease associated with the acquisition of Davenport. ( See Note 3 - Acquisitions ). Future minimum lease payments under non-cancelable capital leases were as follows