Balance Sheet and Cash Flow Supplemental Information - Schedule of Additional Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Supplemental non cash information:
Operating activities - Chloride slag inventory purchases made from AMIC (including VAT)	$ 11	$ 18
Operating activities - MGT sales made to AMIC	2	2
Investing activities - In-kind receipt of AMIC loan repayment	11	18
Financing activities - Repayment of MGT loan	2	$ 2
Capital expenditures acquired but not yet paid	$ 51		$ 91

Related Party Sales

No definition available.

Name:	trox_RelatedPartySales
Namespace Prefix:	trox_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Future cash outflow to pay for purchases of fixed assets that have occurred.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482913/230-10-50-4

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482913/230-10-50-3

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482913/230-10-50-5

+ Details

Name:	us-gaap_CapitalExpendituresIncurredButNotYetPaid
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- References

No definition available.

+ Details

Name:	us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The value of notes retired (or transferred to another entity) in noncash investing or financing transactions.

+ References

+ Details

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

- Definition

Amount of cash outflow for acquisition of investment, classified as operating activity. Includes, but is not limited to, funding, origination, drawdown, and participation in investment.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 946
-SubTopic 230
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477867/946-230-45-1

+ Details

Name:	us-gaap_PaymentsForPurchaseOfInvestmentOperatingActivity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash inflow associated with the collection, including prepayments, of loans receivable issued for financing of goods and services.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-12

+ Details

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