XML 113 R101.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Employee Benefit Plans (Retiree Medical Coverage) - Additional Information (Detail) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2017 | Dec. 31, 2016
Compensation And Retirement Disclosure [Abstract] |  |
Maximum number of years medical, dental and prescription drug coverage to spouse of deceased officer | 30 years |
Total liability recorded to provide medical, dental and prescription drug coverage | $ 0.1 | $ 0.2

X
- Definition The maximum number of years medical, dental and prescription coverage is extended to the spouse of a former officer. + References No definition available. + Details
Name: | adtn_MaximumPeriodOfMedicalDentalAndPrescriptionDrugCoverage
Namespace Prefix: | adtn_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_CompensationAndRetirementDisclosureAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The carrying amount of the liability as of the balance sheet date to an individual under a deferred compensation arrangement. This amount may be the result of periodic accruals made over the period of active employment, or reflect termination benefits resulting contractual terms or a death benefit. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 710 -SubTopic 10 -Section 30 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6409875&loc=d3e20015-108363 + Details
Name: | us-gaap_DeferredCompensationArrangementWithIndividualRecordedLiability
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant