Carrying value at the balance sheet date of obligations related to unpaid employee termination benefits.

No definition available.

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Namespace Prefix:	cnxn_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The number of office facilities closed.

+ References

No definition available.

+ Details

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Namespace Prefix:	cnxn_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan and other charges incurred outside of the normal course of business.

+ References

No definition available.

+ Details

Name:	cnxn_RestructuringAndOtherCharges
Namespace Prefix:	cnxn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- References

No definition available.

+ Details

Name:	us-gaap_AllowanceForCreditLossAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of increase (decrease) in allowance for credit loss on accounts receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
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- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

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BASIS OF PRESENTATION - Restructuring and Other Charges (Details) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Dec. 31, 2019 facility
Restructuring and other charges
Number of office facilities closed \| facility			1
Restructuring and other charges	$ 992	$ 703
Accrued employee termination benefits	133	216
Customer allowance for doubtful accounts
Increase in customer allowance for doubtful accounts due to COVID-19	3,276	181
Employee separations
Restructuring and other charges
Restructuring and other charges	$ 992	553
Lease termination costs
Restructuring and other charges
Restructuring and other charges		$ 150