Definite-lived intangible assets are amortized over their useful lives and are subject to impairment testing. The values assigned to intangible assets in connection with the Merger Transaction and the acquisitions of Servalite, TagWorks, Ook, and Paulin were determined through separate independent appraisals. In connection with the Merger Transaction, the Company acquired the Quick-Tag™ license for consideration amounting to $11,500. Other intangibles, net as of December 31, 2013 and 2012 consist of the following:

The amortization expense for amortizable assets was $22,112, $21,752, and $20,717 for the years ended December 31, 2013, 2012, and 2011, respectively. For the years ending December 31, 2014, 2015, 2016, 2017, and 2018 the amortization expense for amortizable assets is estimated to be $22,200, $21,539, $19,608, $18,754, and $18,754, respectively.