Note 9 — Goodwill and Intangible Assets, Net

The following table presents details of the Company’s total goodwill:


As of October 1, 2016	$	2,211,639
Goodwill resulting from acquisitions		18,535
Other		(8,965	)

As of September 30, 2017		2,221,209
Goodwill resulting from acquisitions(1)		227,283
Other		(3,597	)

As of September 30, 2018	$	2,444,895

(1)

Mainly relates to the acquisitions of Vubiquity, projekt202 and UXP. In allocating the total preliminary purchase price for Vubiquity, based on estimated fair values, the Company recorded $146,912 of goodwill, $38,630 of customer relationships to be amortized over approximately nine years, $45,692 of core technology to be amortized over approximately five years, $10,104 of trade mark to be amortized over eight years. In allocating the total preliminary purchase price of projekt202, based on estimated fair values, the Company recorded $34,032 of goodwill and $19,835 of customer relationships to be amortized over four years. In allocating the total preliminary purchase price of UXP, based on estimated fair values, the Company recorded $41,468 of goodwill, $31,552 of core technology to be amortized over five years and $6,552 of customer relationships to be amortized over approximately five years.

The Company performs an annual goodwill impairment test during the fourth quarter of each fiscal year, or more frequently if impairment indicators are present. The Company operates in one operating segment, and this segment comprises its only reporting unit. In calculating the fair value of the reporting unit, the Company uses its market capitalization and a discounted cash flow methodology. There was no impairment of goodwill in fiscal years 2018, 2017 or 2016.

The following table presents details regarding the Company’s total definite-lived purchased intangible assets:


	Gross		Accumulated Amortization			Net
September 30, 2018
Core technology	$	721,384	$	(576,936	)	$	144,448
Customer relationships		563,656		(453,137	)		110,519
Intellectual property rights and purchased computer software		51,996		(51,996	)		—
Other		43,646		(33,364	)		10,282

Total	$	1,380,682	$	(1,115,433	)	$	265,249

September 30, 2017
Core technology	$	604,673	$	(513,501	)	$	91,172
Customer relationships		497,296		(414,654	)		82,642
Intellectual property rights and purchased computer software		51,996		(51,996	)		—
Other		33,542		(30,030	)		3,512

Total	$	1,187,507	$	(1,010,181	)	$	177,326

The following table presents the amortization expense of the Company’s definite-lived purchased intangible assets, included in each financial statement caption reported in the consolidated statements of income:


	Year Ended September 30,
	2018		2017		2016
Cost of revenue	$	572	$	1,405	$	1,609
Amortization of definite-lived purchased intangible assets		105,213		108,453		96,465

Total	$	105,785	$	109,858	$	98,074

The estimated future amortization expense of definite-lived purchased intangible assets as of September 30, 2018 is as follows:


	Amount
Fiscal year:
2019	$	92,693
2020		61,527
2021		42,554
2022		30,380
2023		14,682
Thereafter		23,413

Total	$	265,249