Supplemental Balance Sheet Information (Tables)

12 Months Ended

Dec. 31, 2017

Balance Sheet Related Disclosures [Abstract]

Schedule of Accounts Receivable Reserves and Allowances

See the table below for additional information on reserves and allowances.

	Accounts Receivable
	(In millions)
Reserves and Allowances
Balance, as of December 31, 2015	$	0.6
Additions	0.1
Write-offs, net of recoveries	(0.5		)
Balance, as of December 31, 2016	$	0.2
Additions	0.2
Write-offs, net of recoveries	—
Balance, as of December 31, 2017	$	0.4

Schedule of Additional Supplemental Balance Sheet Information

Property, plant and equipment balances as of the years ended December 31, 2017 and 2016 include the following:

	As of December 31,
	2017			2016
	(In millions)
Property, Plant and Equipment
Buildings and leasehold improvements	0.5			$	3.3
Machinery and equipment	10.0			9.4
Total	10.5			12.7
Less accumulated depreciation	(9.7		)	(9.9		)
Property, plant and equipment, net	$	0.8		$	2.8

Schedule of Other Current Liabilities

Other current liabilities (included as a separate line item in our Consolidated Balance Sheets) include the following:

	December 31,
	2017		2016
	(In millions)
Accrued payroll	$	1.5	$	2.6
Deferred revenue	7.2		6.7
Restructuring accruals (Note 7)	0.3		—
Levy accruals	5.6		4.9
Other current liabilities	2.1		1.8
Total other current liabilities	$	16.7	$	16.0