Goodwill

We perform our annual goodwill impairment test during the fourth quarter. If certain factors occur, we may have to perform an impairment test prior to the fourth quarter 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.

The carrying amounts of our goodwill, all in our Electronic Systems segment, were as follows:



	(In thousands)
Gross goodwill	$	164,276
Accumulated goodwill impairment	(81,722		)
Balance at December 31, 2016	82,554
Goodwill from acquisition during the period	34,881
Balance at September 30, 2017	$	117,435