v3.25.3

Cover	Oct. 21, 2025
Entity Addresses [Line Items]
Document Type	8-K
Amendment Flag	false
Document Period End Date	Oct. 21, 2025
Current Fiscal Year End Date	--12-31
Entity File Number	001-42392
Entity Registrant Name	INFLECTION POINT ACQUISITION CORP. IV
Entity Central Index Key	0002028707
Entity Tax Identification Number	98-1797826
Entity Incorporation, State or Country Code	E9
Entity Address, Address Line One	1345 Avenue of the Americas
Entity Address, Address Line Two	Fl 47
Entity Address, City or Town	New York
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	10105
City Area Code	212
Local Phone Number	984-3835
Written Communications	false
Soliciting Material	false
Pre-commencement Tender Offer	false
Pre-commencement Issuer Tender Offer	false
Entity Emerging Growth Company	true
Elected Not To Use the Extended Transition Period	false
Units, each consisting of one Class A ordinary share and one right
Entity Addresses [Line Items]
Title of 12(b) Security	Units, each consisting of one Class A ordinary share and one right
Trading Symbol	BACQU
Security Exchange Name	NASDAQ
Class A ordinary shares, par value $0.0001 per share
Entity Addresses [Line Items]
Title of 12(b) Security	Class A ordinary shares, par value $0.0001 per share
Trading Symbol	BACQ
Security Exchange Name	NASDAQ
Rights, each right entitling the holder to receive one-tenth (1/10) of one Class A ordinary share
Entity Addresses [Line Items]
Title of 12(b) Security	Rights, each right entitling the holder to receive one-tenth (1/10) of one Class A ordinary share
Trading Symbol	BACQR
Security Exchange Name	NASDAQ
Former Address [Member]
Entity Addresses [Line Items]
Entity Information, Former Legal or Registered Name	Bleichroeder Acquisition Corp. I

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Area code of city

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End date of current fiscal year in the format --MM-DD.

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For the EDGAR submission types of Form 8-K: the date of the report, the date of the earliest event reported; for the EDGAR submission types of Form N-1A: the filing date; for all other submission types: the end of the reporting or transition period. The format of the date is YYYY-MM-DD.

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The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'.

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Address Line 1 such as Attn, Building Name, Street Name

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Address Line 2 such as Street or Suite number

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Name of the City or Town

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Code for the postal or zip code

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Name of the state or province.

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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.

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- Definition

A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Exchange Act
-Number 240
-Section 12
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- Definition

Indicate if registrant meets the emerging growth company criteria.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition

Indicate if an emerging growth company has elected not to use the extended transition period for complying with any new or revised financial accounting standards.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition

Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen.

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No definition available.

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Two-character EDGAR code representing the state or country of incorporation.

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Former Legal or Registered Name of an entity

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The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Exchange Act
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The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Local phone number for entity.

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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Title of a 12(b) registered security.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Name of the Exchange on which a security is registered.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as soliciting material pursuant to Rule 14a-12 under the Exchange Act.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Trading symbol of an instrument as listed on an exchange.

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No definition available.

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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as written communications pursuant to Rule 425 under the Securities Act.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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INFLECTION POINT ACQUISITION CORP. IV 8-K