4. Business Acquisitions, Goodwill and Intangible Assets

The Company obtained control of an unconsolidated joint venture that resulted in its consolidation during the six months ended March 31, 2014, as further discussed in Note 6. No other business acquisitions occurred during the six months ended March 31, 2014.

At the time of acquisition, the Company preliminarily estimates the amount of the identifiable intangible assets acquired based upon historical valuations of similar acquisitions and the facts and circumstances available at the time. The Company determines the final value of the identifiable intangible assets as soon as information is available, but not more than 12 months from the date of acquisition. Post-acquisition adjustments primarily relate to project related liabilities.

The changes in the carrying value of goodwill by reportable segment for the six months ended March 31, 2014 and 2013 were as follows:

	September 30, 2013		Post- Acquisition Adjustments		Foreign Exchange Impact			Acquired		March 31, 2014
	(in millions)
Professional Technical Services	$	1,645.0	$	5.0	$	(8.5	)	$	79.1	$	1,720.6
Management Support Services	166.8		—		—			—		166.8
Total	$	1,811.8	$	5.0	$	(8.5	)	$	79.1	$	1,887.4

	September 30, 2012		Post- Acquisition Adjustments		Foreign Exchange Impact			Acquired		March 31, 2013
	(in millions)
Professional Technical Services	$	1,608.6	$	—	$	(15.7	)	$	48.2	$	1,641.1
Management Support Services	166.8		—		—			—		166.8
Total	$	1,775.4	$	—	$	(15.7	)	$	48.2	$	1,807.9

The gross amounts and accumulated amortization of the Company’s acquired identifiable intangible assets with finite useful lives as of March 31, 2014 and September 30, 2013, included in intangible assets—net, in the accompanying consolidated balance sheets, were as follows:

	March 31, 2014							September 30, 2013
	Gross Amount		Accumulated Amortization			Intangible Assets, Net		Gross Amount		Accumulated Amortization			Intangible Assets, Net		Amortization Period
	(in millions)														(years)
Backlog	$	104.4	$	(93.1	)	$	11.3	$	94.9	$	(89.4	)	$	5.5	1 — 5
Customer relationships	158.0		(77.2		)	80.8		147.1		(69.5		)	77.6		10
Trademark / tradename	7.8		(7.8		)	—		7.8		(7.8		)	—		2
Total	$	270.2	$	(178.1	)	$	92.1	$	249.8	$	(166.7	)	$	83.1

Amortization expense of acquired intangible assets included within cost of revenue was $11.4 million and $10.8 million for the six months ended March 31, 2014 and 2013, respectively. The following table presents estimated amortization expense of intangible assets for the remainder of fiscal 2014 and for the succeeding years:

Fiscal Year	(in millions)
2014 (six months remaining)	$	11.6
2015	21.7
2016	15.4
2017	12.9
2018	9.7
Thereafter	20.8
Total	$	92.1