3. Business Acquisitions, Goodwill and Intangible Assets

The Company completed one acquisition during the year ended September 30, 2018 for a total consideration of $5.6 million, which was accounted for under the acquisition method. Acquired tangible and intangible assets and liabilities were recognized on the acquisition date based upon their fair values. The determination of fair values of assets and liabilities acquired requires the Company to make estimates and use valuation techniques when market value is not readily available. Transaction costs associated with business acquisitions are expensed as they are incurred.

In the second quarter of fiscal 2018, management approved a plan to sell non-core oil and gas assets in North America, included in the Company’s Construction Services segment (the Disposal Group). The Company classified the related assets and liabilities of the Disposal Group as held for sale in the consolidated balance sheet. In the third quarter of fiscal 2018, the Company sold a portion of the assets in the Disposal Group and recognized a $2.1 million loss on disposal. The remaining unsold portion of the Disposal Group remains classified as held for sale. The Company recorded losses related to the remeasurement of the Disposal Group based on estimated fair value less costs to sell resulting in total asset impairments of $168.2 million, recorded in Impairment of assets held for sale, including goodwill in the second quarter of fiscal 2018. Fair value was estimated using Level 3 inputs, such as forecasted cash flows, and Level 2 inputs, including bid prices from potential buyers. In connection with the classification of the Disposal Group as held for sale, the Company tested the amount of goodwill and other intangible assets allocated to the Disposal Group for impairment. The Company recorded an impairment of goodwill during the year ended September 30, 2018 of $125.4 million and an impairment of intangible and other noncurrent assets of $42.8 million. As of March 31, 2019, current assets held for sale were primarily comprised of accounts receivable of $37.2 million and property, plant and equipment of $17.5 million. As of March 31, 2019, current liabilities held for sale were primarily comprised of accounts payable of $17.0 million. The Company expects to complete the sale of the remaining Disposal Group assets within the next quarter.

The changes in the carrying value of goodwill by reportable segment for the six months ended March 31, 2019 were as follows:


			Foreign
	September 30,		Exchange		March 31,
	2018		Impact		2019
	(in millions)
Design and Consulting Services	$	3,189.2	$	(9.1)	$	3,180.1
Construction Services		1,008.9		(4.0)		1,004.9
Management Services		1,723.0		0.2		1,723.2
Total	$	5,921.1	$	(12.9)	$	5,908.2

The gross amounts and accumulated amortization of the Company’s acquired identifiable intangible assets with finite useful lives as of March 31, 2019 and September 30, 2018, included in intangible assets—net, in the accompanying consolidated balance sheets, were as follows:


	March 31, 2019						September 30, 2018
	Gross		Accumulated		Intangible		Gross		Accumulated		Intangible		Amortization
	Amount		Amortization		Assets, Net		Amount		Amortization		Assets, Net		Period
	(in millions)												(years)
Backlog and customer relationships	$	1,285.7	$	(1,009.1)	$	276.6	$	1,285.1	$	(966.0)	$	319.1	1	-	11
Trademark / tradename		18.3		(17.7)		0.6		18.3		(17.5)		0.8	0.3	-	2
Total	$	1,304.0	$	(1,026.8)	$	277.2	$	1,303.4	$	(983.5)	$	319.9

Amortization expense of acquired intangible assets included within cost of revenue was $43.3 million and $50.8 million for the six months ended March 31, 2019 and 2018, respectively. The following table presents estimated amortization expense of existing intangible assets for the remainder of fiscal 2019 and for the succeeding years:


Fiscal Year	(in millions)
2019 (six months remaining)	$	41.5
2020		69.6
2021		56.6
2022		43.9
2023		39.5
Thereafter		26.1
Total	$	277.2