Changes In Accounting Policies (Narrative) (Details)	3 Months Ended
Mar. 31, 2018
Hearing Health Direct-to-consumer (DTC) Market [Member]
Trial period	60 days

Contract With Customer, Right Of Return, Trial Period

No definition available.

Name:	iin_ContractWithCustomerRightOfReturnTrialPeriod
Namespace Prefix:	iin_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration