Intangible Assets

12 Months Ended

Sep. 30, 2020

Goodwill And Intangible Assets Disclosure [Abstract]

9. Intangible Assets

Intangible assets consist of the following (in thousands):

		September 30, 2020							September 30, 2019
	Useful Life	Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount		Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount
Customer lists	6 years	$	1,219	$	(1,151	)	$	68	$	1,219	$	(948	)	$	271
Trade names	15 years		869		(328	)		541		869		(270	)		599
		$	2,088	$	(1,479	)	$	609	$	2,088	$	(1,218	)	$	870

In 2018, we conducted our periodic assessment of long-lived assets and identified the need for an intangible asset impairment charge in our Solar segment of $1.3 million due primarily to the decline in our expected performance of that segment. All remaining intangible assets are included in our Semiconductor segment. During 2020, we periodically assessed whether any indicators of impairment existed related to our intangible assets. As of each interim period end during the year, we concluded that a triggering event had not occurred that would more likely than not reduce the fair value of intangible assets below their carrying value.

Amortization expense related to intangible assets at our continuing operations was $0.3 million, $0.3 million and $(20,000) in 2020, 2019 and 2018, respectively. The credit in 2018 was due to a one-time correction of previously recorded amortization expense. Future amortization expense for the remaining unamortized balance as of September 30, 2020, is estimated as follows:

Years Ending September 30,	Amortization Expense
2021	$	126
2022		58
2023		58
2024		58
2025		58
Thereafter		251
Total	$	609