Acquisitions - Acquisition of NII (Details)		1 Months Ended	3 Months Ended	9 Months Ended		12 Months Ended
	Jul. 05, 2017 USD ($) facility	Nov. 08, 2017 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2017 USD ($)	Oct. 01, 2016 USD ($)	Dec. 31, 2016 USD ($)
Business Acquisition [Line Items]
Payments to acquire businesses				$ 204,228,000	$ 56,617,000
Goodwill			$ 264,840,000	$ 264,840,000		$ 151,455,000
NII FPG [Member]
Business Acquisition [Line Items]
Payments to acquire businesses	$ 170,655,000
Post-closing Adjustment	(2,134,000)
Cash Paid to Seller Borrowed Under the Revolving Credit Facility	$ 170,018,000
Number of primary manufacturing facilities | facility	2
Revenues reported by acquired entity						$ 81,000,000
Goodwill	$ 84,606,000
Goodwill expected to be deductible for tax purposes	32,990,000
Revenues from the date of acquisition			26,668,000
Total operating income			1,124,000
Amortization expense			4,212,000
NII FPG [Member] | Revolving Credit Facility [Member]
Business Acquisition [Line Items]
Cash Paid to Seller Borrowed Under the Revolving Credit Facility	$ 170,018,000
NII FPG [Member] | Revolving Credit Facility [Member] | Canadian-Denominated Borrowing [Member]
Business Acquisition [Line Items]
Cash Paid to Seller Borrowed Under the Revolving Credit Facility			62,690,000
NII FPG [Member] | Revolving Credit Facility [Member] | Euro-Denominated Borrowing [Member]
Business Acquisition [Line Items]
Cash Paid to Seller Borrowed Under the Revolving Credit Facility			$ 61,769,000
NII FPG [Member] | Subsequent Event [Member]
Business Acquisition [Line Items]
Post-closing Adjustment		$ (2,134,000)