Contingencies - Additional Information (Details) $ in Thousands				1 Months Ended	3 Months Ended		9 Months Ended						12 Months Ended		36 Months Ended
	Mar. 08, 2017 USD ($)	Feb. 09, 2017 USD ($)	Oct. 06, 2016 USD ($) policy	Aug. 31, 2017 USD ($)	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($) LegalMatter	Sep. 30, 2017 USD ($) LegalMatter	Sep. 30, 2017 USD ($) LegalMatter	Sep. 30, 2017 USD ($) LegalMatter	Sep. 30, 2017 USD ($) LegalMatter Vendor	Sep. 30, 2017 USD ($) LegalMatter category	Sep. 30, 2016 USD ($)	Dec. 31, 2010 policy	Dec. 31, 2009 policy	Dec. 31, 2015 USD ($) LegalMatter	Dec. 31, 2016 USD ($) LegalMatter
Loss Contingencies [Line Items]
Number of main categories of product liability claims | category											2
Cumulative trauma liability claims, term							3 years
Loss contingency, years of activity							5 years
Number of insurance carriers								3		20
Insurance receivables						$ 108,700	$ 108,700	$ 108,700	$ 108,700	$ 108,700	$ 108,700				$ 229,500	$ 159,900
Insurance receivables, current						10,500	10,500	10,500	10,500	10,500	10,500					2,000
Insurance receivables, noncurrent						98,200	98,200	98,200	98,200	98,200	98,200					157,900
Notes receivable from insurance companies						78,400	78,400	78,400	78,400	78,400	78,400				$ 8,700	67,300
Notes receivable from insurance companies, current						19,295	19,295	19,295	19,295	19,295	19,295					4,180
Notes receivable from insurance companies, noncurrent						59,151	59,151	59,151	59,151	59,151	59,151					63,147
Attorneys' fees		$ 11,800
Payment received pursuant to insurance policies	$ 80,900
Single Incident
Loss Contingencies [Line Items]
Product liability accrual						$ 3,700	$ 3,700	$ 3,700	3,700	$ 3,700	$ 3,700					$ 3,400
Product liability expense									$ 300			$ 500
Lawsuit
Loss Contingencies [Line Items]
Number of lawsuits | LegalMatter						1,435	1,435	1,435	1,435	1,435	1,435				1,988	1,794
Damages from Product Defects
Loss Contingencies [Line Items]
Number of lawsuits | LegalMatter						2,271	2,271	2,271	2,271	2,271	2,271				3,779	3,023
Cumulative Trauma
Loss Contingencies [Line Items]
Product liability accrual						$ 91,600	$ 91,600	$ 91,600	$ 91,600	$ 91,600	$ 91,600
Product liability expense									101,400						$ 150,900
Uninsured Cumulative Trauma
Loss Contingencies [Line Items]
Product liability expense									33,000
Other Current Liabilities | Cumulative Trauma
Loss Contingencies [Line Items]
Product liability accrual						63,000	63,000	63,000	63,000	63,000	63,000					$ 11,100
Other Noncurrent Liabilities | Cumulative Trauma
Loss Contingencies [Line Items]
Product liability accrual						28,600	$ 28,600	$ 28,600	$ 28,600	$ 28,600	$ 28,600
North River Insurance Company
Loss Contingencies [Line Items]
Gain contingency, number of policies allegedly breached | policy			3										3	1
Litigation Settlement, Amount Awarded from Other Party			$ 10,900
Damages awarded		46,900
Pre-judgment interest		5,100
North River Insurance Company | Punitive Damages
Loss Contingencies [Line Items]
Damages awarded		$ 30,000
Settled Litigation
Loss Contingencies [Line Items]
Payments to resolve cumulative trauma claims						$ 3,200
Damages awarded				$ 75,200
Settled Litigation | Scenario, Forecast
Loss Contingencies [Line Items]
Payments to resolve cumulative trauma claims					$ 22,000