Basis of Presentation and Recently Issued Accounting Standards - Additional Information (Detail) - Segment	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2020
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Number of operating segments	3	3
VNext [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Business acquisition, effective date of acquisition		Feb. 28, 2020
PCM [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Business acquisition, effective date of acquisition		Aug. 30, 2019

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8672-108599

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Balance Type:	na
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