Line of Credit Facility, Accordion Feature, Increase Limit

No definition available.

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

- Definition

Private Placement Issuance Period

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

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+ Details

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

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Date the credit facility terminates, in YYYY-MM-DD format.

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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
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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+ Details

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Balance Type:	credit
Period Type:	instant

- Details

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Balance Type:
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- Details

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- Details

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Balance Type:
Period Type:

- Details

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Balance Type:
Period Type:

- Details

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Balance Type:
Period Type:

- Details

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Balance Type:
Period Type:

- Details

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Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Balance Type:
Period Type:

- Details

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Debt (Narrative) (Details) - USD ($)	3 Months Ended		12 Months Ended
Debt (Narrative) (Details) - USD ($)	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Line of Credit Facility [Line Items]
Short-term borrowings	$ 107,800,000		$ 31,600,000
Interest expense, net	900,000	$ 800,000
Letters of credit outstanding	7,800,000		7,800,000
Minimum
Line of Credit Facility [Line Items]
Short-term borrowings	0	33,100,000
Maximum
Line of Credit Facility [Line Items]
Short-term borrowings	107,800,000	$ 173,100,000
Amended Credit Agreement
Line of Credit Facility [Line Items]
Remaining borrowing capacity	$ 640,700,000		718,100,000
Credit agreement commitment fee percentage	0.40%
Short-term borrowings	$ 107,400,000		30,000,000.0
Letters of credit outstanding	$ 1,900,000		1,900,000
Prudential Private Placement Shelf Agreement
Line of Credit Facility [Line Items]
Debt maturity date	Aug. 01, 2023
Issuance period	3 years
Unused borrowing capacity, amount	$ 100,000,000.0
MetLife Private Placement Shelf Agreement
Line of Credit Facility [Line Items]
Debt maturity date	Jun. 01, 2024
Issuance period	3 years
Unused borrowing capacity, amount	$ 150,000,000.0
Prudential Shelf Agreement Or MetLife Shelf Agreement
Line of Credit Facility [Line Items]
Notes issued face amount	$ 0		0
Line of credit \| Amended Credit Agreement \| Revolving Credit Facility
Line of Credit Facility [Line Items]
Maximum borrowing capacity			750,000,000.0
Accordion feature, increase limit			$ 375,000,000.0
Expiration date			Aug. 01, 2026
Debt instrument, term			5 years
Line of credit \| Amended Credit Agreement \| Letter of Credit Sub-Facility
Line of Credit Facility [Line Items]
Maximum borrowing capacity			$ 25,000,000.0
Line of credit \| Amended Credit Agreement \| Bridge Loan \| Graybar Canada
Line of Credit Facility [Line Items]
Maximum borrowing capacity			100,000,000.0
Line of credit \| Amended Credit Agreement \| Bridge Loan \| UNITED STATES
Line of Credit Facility [Line Items]
Maximum borrowing capacity			75,000,000.0
Line of credit \| Amended Credit Agreement \| Bridge Loan \| CANADA
Line of Credit Facility [Line Items]
Maximum borrowing capacity			$ 20,000,000.0