STOCK-BASED COMPENSATION - SCHEDULE OF EMPLOYEE STOCK PURCHASE PLAN (Detail) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Shares purchased under ESPP (in shares)	26,689	48,750
Average price of shares purchased under ESPP (in dollars per share)	$ 8.17
Intrinsic value of shares purchased under ESPP	$ 106

Amount of difference between the market value on the date of purchase and the purchase price of the shares purchased under ESPP.

No definition available.

+ Details

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Namespace Prefix:	immr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

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- Definition

The weighted average of per share prices paid for shares purchased on the open market for issuance to employees under the plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5047-113901

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Period Type:	instant

- Definition

The number of shares purchased on the open market during the period for issuance to employees under the plan.

+ References

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