Goodwill and Other Intangible Assets

The Company records as goodwill the excess of purchase price over the fair value of the identifiable net assets acquired. Impairment testing is performed annually, as well as when an event triggering impairment may have occurred. The Company performs its annual analysis as of June 30 each fiscal year. Accounting guidance permits preliminary assessment of qualitative factors to determine whether more substantial impairment testing is required. The Company chose to bypass the preliminary assessment and utilized a two-step process for impairment testing of goodwill. The first step tests for impairment, while the second step, if necessary, measures the impairment. No indicators of impairment were identified during the years ended December 31, 2019, 2018, or 2017.

Core deposit intangibles resulting from the MidCarolina acquisition in July 2011 were $6,556,000 and are being amortized on an accelerated basis over 108 months. Core deposit intangibles resulting from the MainStreet Bankshares, Inc. acquisition in January 2015 were $1,839,000 and are being amortized on an accelerated basis over 120 months. Core deposit intangibles resulting from the acquisition of HomeTown in April 2019 were $8,200,000 and are being amortized on an accelerated basis over 120 months.

The changes in the carrying amount of goodwill and intangibles for the twelve months ended December 31, 2019, are as follows (dollars in thousands):



	Goodwill		Intangibles
Balance at December 31, 2018	$	43,872	$	926
Additions	40,130		8,200
Amortization	—		(1,398		)
Balance at December 31, 2019	$	84,002	$	7,728

Goodwill and intangible assets at December 31, 2019 and 2018 are as follow (dollars in thousands):



	Gross Carrying Value		Accumulated Amortization			Net Carrying Value
December 31, 2019
Core deposit intangibles	$	19,708	$	(11,980	)	$	7,728
Goodwill	84,002		—			84,002

December 31, 2018
Core deposit intangibles	$	11,508	$	(10,582	)	$	926
Goodwill	43,872		—			43,872

Amortization expense of core deposit intangibles for the years ended December 31, 2019, 2018, and 2017 was $1,398,000, $265,000, and $528,000, respectively. As of December 31, 2019, the estimated future amortization expense of core deposit intangibles is as follows (dollars in thousands):



Year	Amount
2020	$	1,637
2021	1,464
2022	1,260
2023	1,069
2024	800
2025 and after	1,498
Total	$	7,728