VORNADO REALTY TRUST | 2013 | FY | 3


9. Identified Intangible Assets and Liabilities

The following summarizes our identified intangible assets (primarily acquired above-market leases) and liabilities (primarily acquired below-market leases) as of December 31, 2013 and 2012.

 

   Balance as of December 31, 
 (Amounts in thousands)2013 2012 
 Identified intangible assets:      
 Gross amount$ 605,915 $ 767,365 
 Accumulated amortization  (282,593)   (352,035) 
 Net$ 323,322 $ 415,330 
 Identified intangible liabilities (included in deferred revenue):      
 Gross amount$ 892,487 $ 902,525 
 Accumulated amortization  (382,002)   (341,536) 
 Net$ 510,485 $ 560,989 

Amortization of acquired below-market leases, net of acquired above-market leases resulted in an increase to rental income of $52,861,000, $54,215,000 and $61,869,000 for the years ended December 31, 2013, 2012 and 2011, respectively. Estimated annual amortization of acquired below-market leases, net of acquired above-market leases for each of the five succeeding years commencing January 1, 2014 is as follows:

 (Amounts in thousands)   
 2014$ 45,588 
 2015  42,095 
 2016  40,489 
 2017  35,173 
 2018  33,408 

Amortization of all other identified intangible assets (a component of depreciation and amortization expense) was $64,330,000, $49,597,000 and $52,632,000 for the years ended December 31, 2013, 2012 and 2011, respectively. Estimated annual amortization of all other identified intangible assets including acquired in-place leases, customer relationships, and third party contracts for each of the five succeeding years commencing January 1, 2014 is as follows:

 (Amounts in thousands)   
 2014$ 29,238 
 2015  23,869 
 2016  20,689 
 2017  17,260 
 2018  12,860 

We are a tenant under ground leases at certain properties. Amortization of these acquired below-market leases, net of above-market leases resulted in an increase to rent expense of $4,357,000, $1,328,000 and $993,000 for the years ended December 31, 2013, 2012 and 2011, respectively. Estimated annual amortization of these below-market leases, net of above-market leases for each of the five succeeding years commencing January 1, 2014 is as follows:

 

 (Amounts in thousands)   
 2014$ 3,430 
 2015  3,430 
 2016  3,430 
 2017  3,430 
 2018  3,430 

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