Discontinued Operations (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Summary of the Impact on Net Sales, Net Loss and Loss Per Share from Discontinued Operations
Net loss from discontinued operations	$ (2,800,000)	$ (7,400,000)	$ (37,100,000)	$ (35,900,000)
Net loss per share – basic and diluted (in dollars per share)	$ (0.08)	$ (0.20)	$ (1.00)	$ (0.97)
NATG
Summary of the Impact on Net Sales, Net Loss and Loss Per Share from Discontinued Operations
Net sales	$ 0	$ 0	$ 0	$ 12,000,000
Net loss from discontinued operations	(2,600,000)	(300,000)	(8,700,000)	(21,900,000)
Total Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Special charges			28,600,000
Total Discontinued Operations | SARL
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Special charges	300,000
Transitional services agreement charges	200,000		500,000
Loss on the sale of business			24,400,000
Loss on sale of net assets			8,200,000
Translation adjustments			14,400,000
Legal, professional and other costs			1,000,000
Severance and other personnel costs			300,000
Summary of the Impact on Net Sales, Net Loss and Loss Per Share from Discontinued Operations
Net sales	0	124,600,000	117,000,000	402,700,000
Cost of sales	0	111,500,000	102,900,000	356,800,000
Gross profit	0	13,100,000	14,100,000	45,900,000
Selling, distribution & administrative expenses	2,400,000	20,300,000	22,400,000	73,500,000
Special charges	300,000	(300,000)	28,600,000	9,000,000
Operating loss from discontinued operations	(2,700,000)	(6,900,000)	(36,900,000)	(36,600,000)
Interest and other income, net	300,000	0	800,000	(1,100,000)
Loss from discontinued operations before income taxes	(3,000,000)	(6,900,000)	(37,700,000)	(35,500,000)
Provision for (benefit from) income taxes	(200,000)	500,000	(600,000)	400,000
Net loss from discontinued operations	$ (2,800,000)	$ (7,400,000)	$ (37,100,000)	$ (35,900,000)
Net loss per share – basic and diluted (in dollars per share)	$ (0.08)	$ (0.20)	$ (1.00)	$ (0.97)
Total Discontinued Operations | NATG
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Special charges			$ 3,500,000
Professional costs related to ongoing restitution proceedings	$ 100,000		$ 700,000