Acquisitions - Other Acquisitions (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended		12 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Business Acquisition [Line Items]
Payments to Acquire Businesses, Net of Cash Acquired				$ 67,030	$ 0
Net sales	$ 239,370		$ 224,910	460,660	$ 442,010
Non-cash purchase accounting related expenses	200			1,200
Taplast S.p.A. [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Net of Cash Acquired	44,600
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	$ 200			$ 300