Intangible Assets

12 Months Ended

Sep. 30, 2016

Goodwill and Intangible Assets Disclosure [Abstract]

Intangible Assets

The table below provides details of acquired intangible assets:

	September 30, 2016							September 30, 2015
	Gross		Accumulated Amortization			Net		Gross		Accumulated Amortization			Net
(In millions)
Customer relationships	$	80.4	$	(19.5	)	$	60.9	$	79.6	$	(15.5	)	$	64.1
Patents and technology	46.4		(34.2		)	12.2		46.4		(30.6		)	15.8
Other	3.2		(1.5		)	1.7		3.1		(1.4		)	1.7
Total Intangible Assets	$	130.0	$	(55.2	)	$	74.8	$	129.1	$	(47.5	)	$	81.6

The intangible assets primarily pertain to the Materials segment and have a remaining useful life of approximately 18 years for customer relationships and 6 years for patents and technology.

Amortization expense for intangible assets was $7.5 million, $8.8 million, and $11.2 million in 2016, 2015, and 2014, respectively.

Projected annual amortization expense for intangible assets as of September 30, 2016 is as follows:

2017	$	7.5
2018	6.5
2019	5.3
2020	5.2
2021	5.2
Thereafter	45.1
Total	$	74.8