Debt instrument default interest rate percentage.

No definition available.

Name:	adtn_DebtInstrumentDefaultInterestRatePercentage
Namespace Prefix:	adtn_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Fixed charge coverage ratio.

+ References

No definition available.

+ Details

Name:	adtn_FixedChargeCoverageRatio
Namespace Prefix:	adtn_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- Definition

Line of credit facility floor rate

+ References

No definition available.

+ Details

Name:	adtn_LineOfCreditFacilityFloorRate
Namespace Prefix:	adtn_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Net leverage ratio.

+ References

No definition available.

+ Details

Name:	adtn_NetLeverageRatio
Namespace Prefix:	adtn_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage available for borrowing.

+ References

No definition available.

+ Details

Name:	adtn_PercentageAvailableForBorrowing
Namespace Prefix:	adtn_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Threshold prepayments of outstanding loans german commitment reduction amount.

+ References

No definition available.

+ Details

Name:	adtn_ThresholdPrepaymentsOfOutstandingLoansGermanCommitmentReductionAmount
Namespace Prefix:	adtn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 55
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482949/835-30-55-8

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 69B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481568/470-20-55-69B

Reference 4: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 69C
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481568/470-20-55-69C

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482900/835-30-50-1

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482925/835-30-45-2

+ Details

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

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481544/470-10-50-6

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22)(b))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

+ Details

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

- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtWeightedAverageInterestRate
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-SubTopic 10
-Topic 210
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16)(a)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1

+ Details

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

- Definition

Average amount borrowed under the credit facility during the period.

+ References

No definition available.

+ Details

Name:	us-gaap_LineOfCreditFacilityAverageOutstandingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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

Name:	us-gaap_LineOfCreditFacilityCommitmentFeePercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22)(b))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19)(b))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

+ Details

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

- 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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481544/470-10-50-6

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481544/470-10-50-6

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(f))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

+ Details

Name:	us-gaap_LineOfCreditFacilityLineItems
Namespace Prefix:	us-gaap_
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.

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481544/470-10-50-6

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22)(b))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19)(b))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

+ Details

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

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_SecuredOvernightFinancingRateSofrOvernightIndexSwapRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_BaseRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=adtn_EuroInterbankOfferedRateEuriborMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=adtn_DelayedDrawTermLoanInterestRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=adtn_WellsFargoCreditAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ShortTermDebtTypeAxis=us-gaap_FederalReserveBankAdvancesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=adtn_WellsFargoCreditAgreementAmendmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ShortTermDebtTypeAxis=us-gaap_DelayedDrawTermLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BusinessAcquisitionAxis=adtn_AcornHoldcoIncorporationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=adtn_WellsFargoCreditAgreementSublineMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=adtn_WellsFargoCreditAgreementUSBorrowerMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementScenarioAxis=srt_ScenarioForecastMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementScenarioAxis=adtn_FirstQuarterEndingSpringingCovenantPeriodMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementScenarioAxis=adtn_SecondQuarterEndingSpringingCovenantEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementScenarioAxis=adtn_ThirdAndFourthQuartersEndingSpringingCovenantEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementScenarioAxis=adtn_FromDecemberThirtyFirstTwoThousandTwentyThreeThroughAndIncludingMarchThirtyFirstTwoThousandTwentyFourMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementScenarioAxis=adtn_FromAprilFirstTwoThousandTwentyFourThroughAndIncludingJuneThirtyTwoThousandTwentyFourMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementScenarioAxis=adtn_FromJulyFirstTwoThousandTwentyFourAndThereafterMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Credit Agreements - Additional Information (Detail) $ in Thousands						3 Months Ended	6 Months Ended
	Jun. 30, 2025 USD ($)	Dec. 31, 2024 USD ($)	Jun. 04, 2024 USD ($)	Aug. 09, 2023 USD ($)	Jul. 18, 2022 USD ($)	Dec. 31, 2023 USD ($)	Jun. 30, 2024 USD ($)
Line Of Credit Facility [Line Items]
Weighted average interest rate							8.51%
Revolving line of credit						$ 195,000	$ 190,273
Debt instrument default interest rate percentage							2.00%
Daily Simple SOFR [Member]
Line Of Credit Facility [Line Items]
Credit facility, floor rate							0.00%
Applicable margin rate							3.15%
Base Rate [Member]
Line Of Credit Facility [Line Items]
Applicable margin rate							2.15%
EURIBOR [Member]
Line Of Credit Facility [Line Items]
Credit facility, floor rate							0.00%
Applicable margin rate							3.25%
Maximum [Member] \| Daily Simple SOFR [Member]
Line Of Credit Facility [Line Items]
Applicable margin rate							2.65%
Maximum [Member] \| Base Rate [Member]
Line Of Credit Facility [Line Items]
Applicable margin rate							1.65%
Maximum [Member] \| EURIBOR [Member]
Line Of Credit Facility [Line Items]
Applicable margin rate							2.75%
Minimum [Member] \| Daily Simple SOFR [Member]
Line Of Credit Facility [Line Items]
Applicable margin rate							1.65%
Minimum [Member] \| Base Rate [Member]
Line Of Credit Facility [Line Items]
Applicable margin rate							0.65%
Minimum [Member] \| EURIBOR [Member]
Line Of Credit Facility [Line Items]
Applicable margin rate							1.75%
DDTL Interest Rate [Member]
Line Of Credit Facility [Line Items]
Debt instrument default interest rate percentage							2.00%
Wells Fargo Credit Agreement [Member]
Line Of Credit Facility [Line Items]
Revolving line of credit						$ 195,000	$ 190,273
Commitment fee percentage							0.25%
Wells Fargo Credit Agreement [Member] \| Daily Simple SOFR [Member]
Line Of Credit Facility [Line Items]
Applicable margin rate							0.10%
Wells Fargo Credit Agreement [Member] \| Maximum [Member]
Line Of Credit Facility [Line Items]
Commitment fee percentage							0.25%
Net leverage ratio						0.05	0.05
Wells Fargo Credit Agreement [Member] \| Minimum [Member]
Line Of Credit Facility [Line Items]
Commitment fee percentage							0.20%
Fixed charge coverage ratio						0.0125	0.0125
Wells Fargo Credit Agreement [Member] \| Federal Reserve Bank Advances [Member]
Line Of Credit Facility [Line Items]
Applicable margin rate							1.00%
Wells Fargo Credit Agreement [Member] \| Federal Reserve Bank Advances [Member] \| Daily Simple SOFR [Member]
Line Of Credit Facility [Line Items]
Applicable margin rate							1.00%
Wells Fargo Credit Agreement [Member] \| Federal Reserve Bank Advances [Member] \| Base Rate [Member]
Line Of Credit Facility [Line Items]
Applicable margin rate							1.00%
Wells Fargo Credit Agreement [Member] \| DDTL Interest Rate [Member]
Line Of Credit Facility [Line Items]
Commitment fee percentage							0.25%
Wells Fargo Credit Agreement [Member] \| DDTL Interest Rate [Member] \| Daily Simple SOFR [Member]
Line Of Credit Facility [Line Items]
Applicable margin rate							3.40%
Wells Fargo Credit Agreement [Member] \| DDTL Interest Rate [Member] \| Base Rate [Member]
Line Of Credit Facility [Line Items]
Applicable margin rate							2.40%
Wells Fargo Credit Agreement [Member] \| DDTL Interest Rate [Member] \| Maximum [Member] \| Daily Simple SOFR [Member]
Line Of Credit Facility [Line Items]
Applicable margin rate							2.90%
Wells Fargo Credit Agreement [Member] \| DDTL Interest Rate [Member] \| Maximum [Member] \| Base Rate [Member]
Line Of Credit Facility [Line Items]
Applicable margin rate							1.90%
Wells Fargo Credit Agreement [Member] \| DDTL Interest Rate [Member] \| Minimum [Member] \| Daily Simple SOFR [Member]
Line Of Credit Facility [Line Items]
Applicable margin rate							1.90%
Wells Fargo Credit Agreement [Member] \| DDTL Interest Rate [Member] \| Minimum [Member] \| Base Rate [Member]
Line Of Credit Facility [Line Items]
Applicable margin rate							0.90%
Wells Fargo Credit Agreement Amendment [Member]
Line Of Credit Facility [Line Items]
Secured revolving credit facility amount							$ 50,000
Aggregate principal amount				$ 172,500
Wells Fargo Credit Agreement Amendment [Member] \| Maximum [Member]
Line Of Credit Facility [Line Items]
Revolving line of credit							300,000
Wells Fargo Credit Agreement Amendment [Member] \| Minimum [Member]
Line Of Credit Facility [Line Items]
Aggregate principal amount							$ 75,000
Net leverage ratio							0.035
Wells Fargo Credit Agreement Amendment [Member] \| Delayed Draw Term Loan [Member]
Line Of Credit Facility [Line Items]
Revolving line of credit				$ 50,000	$ 50,000
Percentage available for borrowing				60.00%
Acorn HoldCo, Inc., [Member] \| Wells Fargo Credit Agreement [Member]
Line Of Credit Facility [Line Items]
Secured revolving credit facility amount					400,000		$ 400,000
Revolving line of credit							190,300
Credit facility, average outstanding amount							3,700
Letters of credit may be utilize							50,000
Available for future borrowings							206,000
Credit agreement current borrowing capacity							16,400
Acorn HoldCo, Inc., [Member] \| Wells Fargo Credit Agreement Amendment [Member]
Line Of Credit Facility [Line Items]
Secured revolving credit facility amount			$ 400,000
Acorn HoldCo, Inc., [Member] \| Wells Fargo Credit Agreement - Subline [Member]
Line Of Credit Facility [Line Items]
Revolving line of credit							75,300
Threshold prepayments of outstanding loans german commitment reduction amount			75,000
Credit facility, average outstanding amount			$ 100,000		$ 100,000
Acorn HoldCo, Inc., [Member] \| Wells Fargo Credit Agreement - US Borrower [Member]
Line Of Credit Facility [Line Items]
Revolving line of credit							$ 115,000
Scenario Forecast [Member] \| EURIBOR [Member]
Line Of Credit Facility [Line Items]
Applicable margin rate	1.00%	1.00%
Scenario Forecast [Member] \| DDTL Interest Rate [Member]
Line Of Credit Facility [Line Items]
Applicable margin rate	1.00%	1.00%
Scenario Forecast [Member] \| Wells Fargo Credit Agreement [Member]
Line Of Credit Facility [Line Items]
Secured revolving credit facility amount	$ 300,000	$ 340,000
Scenario Forecast [Member] \| Wells Fargo Credit Agreement [Member] \| DDTL Interest Rate [Member]
Line Of Credit Facility [Line Items]
Secured revolving credit facility amount	$ 300,000	$ 340,000
First Quarter Ending Springing Covenant Period [Member] \| Wells Fargo Credit Agreement [Member]
Line Of Credit Facility [Line Items]
Net leverage ratio							0.04
Second Quarter Ending Springing Covenant Event [Member] \| Wells Fargo Credit Agreement [Member]
Line Of Credit Facility [Line Items]
Net leverage ratio							0.0375
Third and Fourth Quarters Ending Springing Covenant Event [Member] \| Wells Fargo Credit Agreement [Member]
Line Of Credit Facility [Line Items]
Net leverage ratio							0.035
From December 31, 2023 Through and Including March 31, 2024 [Member] \| Wells Fargo Credit Agreement [Member]
Line Of Credit Facility [Line Items]
Net leverage ratio							0.0325
From April 1, 2024 Through and Including June 30, 2024 [Member] \| Wells Fargo Credit Agreement [Member]
Line Of Credit Facility [Line Items]
Net leverage ratio							0.035
From July 1, 2024 and Thereafter [Member] \| Wells Fargo Credit Agreement [Member]
Line Of Credit Facility [Line Items]
Net leverage ratio							0.0325