Intangible Assets and Goodwill (Tables)

6 Months Ended

Jun. 30, 2017

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Intangible Assets

(In millions)	Capacity Agreement			Developed Technology			Total
June 30, 2017
Cost	$	10.1		$	4.3		$	14.4
Accumulated amortization	(0.9		)	(1.2		)	(2.1		)
Intangible assets, net	$	9.2		$	3.1		$	12.3
December 31, 2016
Cost	$	—		$	4.3		$	4.3
Accumulated amortization	—			(0.9		)	(0.9		)
Intangible assets, net	$	—		$	3.4		$	3.4

Schedule of Amortization Expense for Intangible Assets

Amortization expense for intangible assets consisted of the following:

	Three Months Ended				Six Months Ended
	June 30,				June 30,
(In millions)	2017		2016		2017		2016
Amortization expense	$	0.7	$	0.2	$	1.2	$	0.4

Schedule of Intangible Assets Estimated Amortization Expense

Estimated amortization expense for the remainder of 2017 and each of the next four years is as follows:

(In millions)	2017 (Remainder)		2018		2019		2020		2021
Amortization expense	$	1.4	$	2.7	$	2.7	$	2.7	$	2.6