Goodwill

We perform our annual goodwill impairment test during the fourth quarter. If certain factors occur, including significant under performance of our business relative to expected operating results, significant adverse economic and industry trends, significant decline in our market capitalization for an extended period of time relative to net book value, a decision to divest individual businesses within a reporting unit, or a decision to group individual businesses differently, we may perform an impairment test prior to the fourth quarter.

The increase in goodwill in Structural Systems was due to the acquisition of CTP on April 23, 2018. See Note 3.

The carrying amounts of our goodwill were as follows:



	(In thousands)
	Structural Systems		Electronic Systems			Consolidated Ducommun
Gross goodwill	$	—	$	199,157		$	199,157
Accumulated goodwill impairment	—		(81,722		)	(81,722		)
Balance at December 31, 2017	—		117,435			117,435
Goodwill from acquisition during the period	18,334		—			18,334
Balance at September 29, 2018	$	18,334	$	117,435		$	135,769