Other Assets

Other assets as of August 31, 2019 and 2018, are as follows:



	2019		2018
	(Dollars in thousands)
Goodwill	$	172,404	$	138,464
Customer lists, trademarks and other intangible assets	71,206		29,338
Notes receivable	189,045		211,986
Long-term derivative assets	36,408		23,084
Prepaid pension and other benefits	73,100		101,539
Capitalized major maintenance	286,890		130,780
Cash value life insurance	122,792		123,010
Other	60,350		76,128
Total other assets	$	1,012,195	$	834,329

Changes in the net carrying amount of goodwill for the years ended August 31, 2019 and 2018, by segment, are as follows:



	Energy		Ag			Corporate and Other		Total
	(Dollars in thousands)
Balances, August 31, 2017	$	552	$	127,328		$	10,574	$	138,454
Effect of foreign currency translation adjustments	—		10			—		10
Balances, August 31, 2018	552		127,338			10,574		138,464
Goodwill acquired during the period	—		61,358			—		61,358
Impairment	—		(27,418		)	—		(27,418		)
Balances, August 31, 2019	$	552	$	161,278		$	10,574	$	172,404

Goodwill of $61.4 million acquired during the third quarter of fiscal 2019 was related to our acquisition of the remaining 75% ownership in West Central Distribution ("WCD") that we did not previously own. See Note 18, Acquisitions, for additional information related to the acquisition. No goodwill has been allocated to our Nitrogen Production segment, which consists of a single investment accounted for under the equity method.

All long-lived assets, including goodwill and other identifiable intangible assets, are evaluated for impairment in accordance with U.S. GAAP. Goodwill is evaluated for impairment annually as of July 31. All long-lived assets, including goodwill, are also evaluated for impairment whenever triggering events or other circumstances indicate the carrying amount of an asset group or reporting unit may not be recoverable.

As a result of our annual goodwill impairment analyses performed as of July 31, 2019, we recorded a goodwill impairment charge of $27.4 million associated with a reporting unit in our Ag segment. The impairment charge primarily resulted from changing market dynamics that have reduced future profitability within the reporting unit, as well as strategy changes and the challenging economic environment in the agriculture industry. The impairment charge was recorded in the reserve and impairment charges (recoveries), net line item in the Consolidated Statements of Operations for the year ended August 31, 2019. No material impairments related to long-lived assets were recorded, and no goodwill impairments were identified as a result of CHS’s annual goodwill analyses performed as of July 31, 2018.

Intangible assets subject to amortization primarily include customer lists, trademarks and non-compete agreements, and are amortized over their respective useful lives (ranging from 2 to 30 years). Intangible assets of $47.2 million were acquired during fiscal 2019 related to the acquisition of the remaining 75% ownership interest in WCD that we did not previously own. See Note 18, Acquisitions, for additional information related to the acquisition. Information regarding intangible assets included in other assets on our Consolidated Balance Sheets is as follows:



	August 31, 2019							August 31, 2018
	Carrying Amount		Accumulated Amortization			Net		Carrying Amount		Accumulated Amortization			Net
	(Dollars in thousands)
Customer lists	$	84,815	$	(17,609	)	$	67,206	$	40,815	$	(13,082	)	$	27,733
Trademarks and other intangible assets	9,736		(5,736		)	4,000		6,536		(4,931		)	1,605
Total intangible assets	$	94,551	$	(23,345	)	$	71,206	$	47,351	$	(18,013	)	$	29,338

Intangible asset amortization expense for the years ended August 31, 2019, 2018 and 2017, was $5.3 million, $3.4 million and $4.3 million, respectively. The estimated annual amortization expense related to intangible assets subject to amortization for the next five years is as follows:



	(Dollars in thousands)
2020	$	5,271
2021	4,874
2022	4,706
2023	4,576
2024	4,576
Thereafter	47,107
Total	$	71,110

Activity related to capitalized major maintenance costs at our refineries for the years ended August 31, 2019, 2018 and 2017, is summarized below:



	Balance at Beginning of Year		Cost Deferred		Amortization			Balance at End of Year
	(Dollars in thousands)
2019	$	130,780	$	224,406	$	(68,296	)	$	286,890
2018	105,006		87,460		(61,686		)	130,780
2017	169,054		3,010		(67,058		)	105,006