Summary Of Significant Accounting Policies [Line Items]

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The amount of LIFO (last in first out) inventory present at the reporting date when inventory is also valued using different valuation methods.

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The percentage of LIFO (last in first out) inventory to total inventory as of the balance sheet date if other than 100 percent.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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Summary of significant accounting policies - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Summary Of Significant Accounting Policies [Line Items]
Carrying value of equity investments	$ 54,339	$ 55,516
Research and development costs	$ 23,300	$ 23,200	$ 21,000
Percentage of LIFO inventory (percent)	13.00%	14.00%
LIFO inventory amount	$ 20,203	$ 18,854
Minimum
Summary Of Significant Accounting Policies [Line Items]
Intangible assets, useful life	3 years
Minimum \| Equipment
Summary Of Significant Accounting Policies [Line Items]
Property plant and equipment, useful life	3 years
Minimum \| Buildings
Summary Of Significant Accounting Policies [Line Items]
Property plant and equipment, useful life	15 years
Maximum
Summary Of Significant Accounting Policies [Line Items]
Intangible assets, useful life	40 years
Maximum \| Equipment
Summary Of Significant Accounting Policies [Line Items]
Property plant and equipment, useful life	11 years
Maximum \| Buildings
Summary Of Significant Accounting Policies [Line Items]
Property plant and equipment, useful life	40 years
Net sales \| Multi-Vendor Supply Chain Finance Arrangement
Summary Of Significant Accounting Policies [Line Items]
Customer concentrations (percent)	9.00%	9.00%
Net sales \| Customer concentration \| Largest customer
Summary Of Significant Accounting Policies [Line Items]
Customer concentrations (percent)	5.00%	4.00%	4.00%
Net sales \| Customer concentration \| Second largest customer
Summary Of Significant Accounting Policies [Line Items]
Customer concentrations (percent)	4.00%	4.00%	3.00%
Receivables \| Customer concentration \| Largest customer
Summary Of Significant Accounting Policies [Line Items]
Customer concentrations (percent)	8.00%	4.00%
Chilean tube
Summary Of Significant Accounting Policies [Line Items]
Percentage ownership of investments accounted for under the cost method (percent)	19.50%
Finland Small Recycling Business
Summary Of Significant Accounting Policies [Line Items]
Percentage ownership of investments accounted for under the cost method (percent)	12.19%