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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 42
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13531-108611

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 825
-SubTopic 10
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-Subparagraph (a)
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Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592

Name:	us-gaap_ConcentrationRiskPercentage1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Concentrations of Risk - Additional Information (Details) - USD ($) $ in Millions	9 Months Ended		12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Concentration Risk [Line Items]
Accounts receivable, net, current	$ 864.6		$ 845.6
Office Depot \| Credit Concentration Risk
Concentration Risk [Line Items]
Accounts receivable, net, current	$ 39.6		$ 76.2
Office Depot \| Total Company Sales Revenue \| Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk, percentage	5.00%	7.00%
Office Depot \| Total Company Receivables \| Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk, percentage	5.00%		9.00%
Paper \| Office Depot \| Paper Segment Sales Revenue \| Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk, percentage	43.00%	50.00%	50.00%