Acquisitions Acquisitions - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Business Acquisition [Line Items]
Payments to Acquire Businesses, Net of Cash Acquired									$ 67,090	$ 0	$ 0
Net sales	$ 170,920	$ 188,410	$ 190,830	$ 173,370	$ 170,090	$ 182,100	$ 181,690	$ 171,150	723,530	705,030	$ 656,160
Non-cash purchase accounting related expenses									1,200
Taplast S.p.A. [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Net of Cash Acquired									44,700
Net sales										32,000
Plastic Srl [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Net of Cash Acquired									22,400
Net sales										$ 12,000
Selling, General and Administrative Expenses [Member]
Business Acquisition [Line Items]
Non-cash purchase accounting related expenses									900
Cost of Sales [Member]
Business Acquisition [Line Items]
Non-cash purchase accounting related expenses									$ 300