Concentrations of Risk - Additional Information (Details) $ in Millions	12 Months Ended
Dec. 31, 2018 USD ($) employee	Dec. 31, 2017 USD ($)
Concentration Risk [Line Items]
Accounts receivable, net, current	$ 901.9	$ 830.7
Number of employees of PCA \| employee	15,000
Percentage of hourly employees represented by unions	63.00%
Workforce Subject to Collective Bargaining Arrangements \| Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk, percentage	44.00%
Workforce Subject to Collective Bargaining Arrangements Expiring within One Year \| Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk, percentage	11.00%
Office Depot \| Credit Concentration Risk
Concentration Risk [Line Items]
Accounts receivable, net, current	$ 66.7	$ 33.3
Office Depot \| Total Company Sales Revenue \| Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk, percentage	7.00%	7.00%
Office Depot \| Total Company Receivables \| Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk, percentage	7.00%	4.00%
Paper \| Office Depot \| Paper Segment Sales Revenue \| Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk, percentage	47.00%	43.00%

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Represents percentage of hourly employees represented by unions.

+ References

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Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

+ References

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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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