Note 6 - Goodwill and Other Intangible Assets

At both December 31, 2018 and 2017, the net carrying value of goodwill was $57.3 million, consisting of goodwill associated with two reporting units. Aggregate other intangible assets amortization expense for the years ended December 31, 2018, 2017, and 2016 was $1.2 million, $1.1 million, and $521 thousand, respectively. As of December 31, 2018, estimated amortization expense associated with other intangible asset balances over each of the next five years is $1.2 million.

As of June 30, 2018, Synovus completed its annual goodwill impairment evaluation applying ASC 350-20-35-3A Goodwill Subsequent Measurement - Qualitative Assessment Approach and concluded that goodwill was not impaired.

The following table shows the carrying amount of goodwill by reporting unit for the year ended December 31, 2018:



(in thousands)	Synovus Bank Reporting Unit		Trust Services Reporting Unit		Total
Balance as of December 31, 2017
Goodwill	$	32,884	$	24,431	$	57,315
Accumulated impairment losses	—		—		—
Balance as of December 31, 2018	$	32,884	$	24,431	$	57,315

The following table shows the gross carrying amount and accumulated amortization of other intangible assets as of December 31, 2018 and 2017. Other intangible assets primarily consist of customer relationship intangibles.



(in thousands)	2018			2017
Other intangible assets, gross carrying amount	$	13,140		$	13,140
Other intangible assets, adjustment	(212		)	—
Other intangible assets, accumulated amortization	(3,053		)	(1,886		)
Other intangible assets, net carrying amount	$	9,875		$	11,254