DESCRIPTION OF THE PLAN - Narrative (Details) - EBP 001	12 Months Ended
Dec. 31, 2025 USD ($) h loan	Dec. 31, 2024 USD ($)
EBP, Description of Plan [Line Items]
Minimum age	18 years
Requisite service period	1 month
Number of hours, part-time employees \| h	1,000
Employer contribution, matching percentage	50.00%
Employer contribution, participant compensation matched, percentage	6.00%
Rollover contributions, vested, percentage	100.00%
Note receivable from participant, account, maximum borrowing, to total account, percentage	50.00%
Maximum borrowing amount, notes receivable from participant	$ 50,000
Minimum borrowing amount, notes receivable from participant	$ 500
Number of loans per participant \| loan	1
Maximum term of notes receivable from participant	5 years
Participant loan, basis spread on variable rate	1.00%
Participant loans defaulted, reclassified to distributions	$ 0	$ 11,471
Minimum
EBP, Description of Plan [Line Items]
Participant contribution, pretax, compensation to eligible compensation, percentage	1.00%
Participant loan, interest rate	4.25%
Maximum
EBP, Description of Plan [Line Items]
Participant contribution, pretax, compensation to eligible compensation, percentage	100.00%
Participant loan, interest rate	9.50%

EBP, Asset Held For Investment, Participant Loan, Default Reclassified To Distribution

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

EBP, Note Receivable From Participant, Maximum Borrowing Term

+ References

No definition available.

+ Details

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- Definition

EBP, Number Of Loans Per Participant

+ References

No definition available.

+ Details

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

- Definition

EBP, Participant Contribution, Pretax, Compensation To Eligible Compensation, Percentage

+ References

No definition available.

+ Details

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Namespace Prefix:	idcc_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Participant Loan, Basis Spread On Variable Rate

+ References

No definition available.

+ Details

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Namespace Prefix:	idcc_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Participant Minimum Age

+ References

No definition available.

+ Details

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Namespace Prefix:	idcc_
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Balance Type:	na
Period Type:	duration

- Definition

EBP, Requisite Number Of Hours, Part Time Employees

+ References

No definition available.

+ Details

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

- Definition

EBP, Requisite Service Period

+ References

No definition available.

+ Details

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

- Definition

EBP, Rollover Contributions, Vested, Percentage

+ References

No definition available.

+ Details

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Namespace Prefix:	idcc_
Data Type:	dtr-types:percentItemType
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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of employer matching contribution on eligible participant contribution to employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 962
-SubTopic 325
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478873/962-325-55-17

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of participant compensation eligible for employer matching contribution for participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow.

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Percentage of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow to total participant account balance.

+ References

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Amount of minimum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow.

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Interest rate on participant loan in schedule of asset held for investment of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 10
-Paragraph b
-Subparagraph (1)(i)(D)
-Publisher DOL-EBSA

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-05(a)(Schedule I))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Details

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- Details

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