Note 17 - Subsequent Event (Details Textual) - Subsequent Event [Member] - USD ($)	1 Months Ended
Feb. 25, 2020	Jan. 31, 2020
Restricted Stock Units (RSUs) and Market Value Stock Units (MVSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	1,247,109
eSilicon [Member]
Payments to Acquire Businesses, Gross		$ 215,000
Business Combination, Maximum Period Consideration Will be Held in Escrow Fund		12 months
Business Combination, Maximum Period Consideration Will Be Held in Escrow Fund in Connection with Recovering under the Buyer-side Representation and Warranty Insurance Policy		36 months

The maximum period the consideration received from a business acquisition will be held in an escrow fund under the indemnification obligation.

No definition available.

+ Details

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

- Definition

Represents the maximum period the consideration received from a business acquisition will be held in an escrow fund in connection with Recovering under the buyer-side representation and warranty insurance policy

+ References

No definition available.

+ Details

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

- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3213-108585

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Balance Type:	credit
Period Type:	duration

- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target 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
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Details

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- Details

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Namespace Prefix:
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Period Type: