In accordance with GAAP, the Company does not amortize goodwill. However, core deposit intangible assets are amortized over the estimated life of the asset. At and intangible assets consisted of core deposit premiums, net of accumulated amortization, and amounted to million and million, respectively. Amortization expense related to the core deposit premium was million, million, and million for the years ended and respectively.

 

Amortization of core deposit intangible assets is computed using the straight-line method over an amortization period of years. Estimated amortization expense for the years ending is as follows (dollars in thousand):

 

 

Goodwill represents the excess of the acquisition cost over the fair value of the net assets acquired. The Company evaluated the carrying value of goodwill as of its annual test date, and determined that no impairment charge was necessary. Should the Company’s future earnings and cash flows decline and/or discount rates increase, an impairment charge to goodwill and other intangible assets be required. There have been no events subsequent to the evaluation that caused the Company to perform an interim review of the carrying value of goodwill. The following table presents a rollforward of goodwill by acquired bank: