Advisory fees expense.

No definition available.

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Namespace Prefix:	cccxu_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Capital markets advisory incentive fee expense.

+ References

No definition available.

+ Details

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Namespace Prefix:	cccxu_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Change of fair value of subscription agreement liability.

+ References

No definition available.

+ Details

Name:	cccxu_ChangeOfFairValueOfSubscriptionAgreementLiability
Namespace Prefix:	cccxu_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Discretionary premium percentage.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Minimum value of consummation of inital business combination.

+ References

No definition available.

+ Details

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Namespace Prefix:	cccxu_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Placement fee maximum limit.

+ References

No definition available.

+ Details

Name:	cccxu_PlacementFeeMaximumLimit
Namespace Prefix:	cccxu_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Placement fee payable.

+ References

No definition available.

+ Details

Name:	cccxu_PlacementFeePayable
Namespace Prefix:	cccxu_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Placement fee percentage.

+ References

No definition available.

+ Details

Name:	cccxu_PlacementFeePercentage
Namespace Prefix:	cccxu_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Subscription agreement expense.

+ References

No definition available.

+ Details

Name:	cccxu_SubscriptionAgreementExpense
Namespace Prefix:	cccxu_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Underwriters deferred fee.

+ References

No definition available.

+ Details

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Namespace Prefix:	cccxu_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Underwriters received upfront compensation expense.

+ References

No definition available.

+ Details

Name:	cccxu_UnderwritersReceivedUpfrontCompensationExpense
Namespace Prefix:	cccxu_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for professional fees, such as for legal and accounting services received. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Number of warrants or rights outstanding.

+ References

No definition available.

+ Details

Name:	us-gaap_ClassOfWarrantOrRightOutstanding
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Face amount or stated value per share of common stock.

+ References

+ Details

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Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

- 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

No definition available.

+ Details

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

- Definition

Amount of liabilities classified as other, due within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
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Reference 2: http://www.xbrl.org/2003/role/exampleRef
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-Name Accounting Standards Codification
-Section 55
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481372/852-10-55-10

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Costs incurred during the period, such as those relating to general administration and policy maintenance that do not vary with and are not primarily related to the acquisition or renewal of insurance contracts.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(7)(b))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477250/944-220-S99-1

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash inflow from the additional capital contribution to the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 14
-Subparagraph (a)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-14

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Value of outstanding derivative securities that permit the holder the right to purchase securities (usually equity) from the issuer at a specified price.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)(i)
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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Data Type:	na
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- Details

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Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=cccxu_SponsorMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_StatementClassOfStockAxis=cccxu_PrivatePlacementUnitsMember
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Data Type:	na
Balance Type:
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Name:	us-gaap_StatementClassOfStockAxis=cccxu_PIPEInvestorsMember
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Name:	us-gaap_StatementClassOfStockAxis=cccxu_DomesticatedSPACCommonStockMember
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Data Type:	na
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Commitments and Contingencies - Additional Information (Detail) - USD ($)				12 Months Ended
	Sep. 08, 2025	Sep. 03, 2025	Sep. 01, 2025	Dec. 31, 2025	Dec. 31, 2024	May 15, 2025	May 13, 2025
Other Commitments [Line Items]
Underwriters deferred fee				$ 3,000,000
Minimum value of consummation of initial business combination				100,000,000
Warrants and rights outstanding				3,000,000		$ 9.923
Sale of stock, price per share						$ 10
Common stock, par value						$ 10
Placement fee percentage			4.00%
Placement fee maximum limit			$ 100,000,000
Placement Fee Payable				0
Change Of Fair Value Of Subscription Agreement Liability				$ 69,585,366	$ 0
Founder Shares [Member]
Other Commitments [Line Items]
Underwriters received upfront compensation expense				360,000
Founder Shares [Member] \| Valuation Technique PWERM Method [Member]
Other Commitments [Line Items]
Warrants and rights outstanding							$ 667,472
Founder Shares [Member] \| Sponsor [Member]
Other Commitments [Line Items]
Class of Warrant or Right, Outstanding				200,000
Private Placement Units [Member] \| Sponsor [Member]
Other Commitments [Line Items]
Class of Warrant or Right, Outstanding				50,000
PIPE Investors [Member]
Other Commitments [Line Items]
Proceeds from issuance of common stock	$ 126,547,600
Sale of stock, price per share	$ 0.0001
Domesticated SPAC Common Stock [Member]
Other Commitments [Line Items]
Common stock, par value	$ 10
Maximum [Member]
Other Commitments [Line Items]
Other Underwriting Expense				$ 3,000,000
Minimum [Member]
Other Commitments [Line Items]
Other Underwriting Expense				1,500,000
Subscription Agreements [Member]
Other Commitments [Line Items]
Other liabilities, current				75,630,352
Subscription agreement expense				6,044,986
Change Of Fair Value Of Subscription Agreement Liability				69,585,366
Capital Markets Advisory Agreement [Member]
Other Commitments [Line Items]
Advisory fees expense		$ 7,000,000
Capital markets advisory incentive fee expense		$ 3,000,000
Advisory Agreement [Member]
Other Commitments [Line Items]
Advisory fees expense				250,000
Legal Fees Agreement [Member]
Other Commitments [Line Items]
Accrued Professional Fees, Current				$ 2,572,053
Legal Fees Agreement [Member] \| Maximum [Member]
Other Commitments [Line Items]
Discretionary Premium Percentage		100.00%
Legal Fees Agreement [Member] \| Minimum [Member]
Other Commitments [Line Items]
Discretionary Premium Percentage		50.00%