Segment Information, Net Sales to External Customers, by Product Segment (Details) $ in Millions	3 Months Ended
Mar. 31, 2017 USD ($) Customer	Mar. 31, 2016 USD ($) Customer
Revenue from External Customer [Line Items]
Net sales	$ 569	$ 476
Pigment [Member]
Revenue from External Customer [Line Items]
Net sales	272	216
Alkali [Member]
Revenue from External Customer [Line Items]
Net sales	191	191
Titanium Feedstock [Member]
Revenue from External Customer [Line Items]
Net sales	92	57
Electrolytic [Member]
Revenue from External Customer [Line Items]
Net sales	$ 14	$ 12
Sales Revenue, Net [Member] \| Customer Concentration Risk [Member] \| 10 Largest Third-party TiO2 Customers [Member]
Revenue, Major Customer [Line Items]
Number of largest customers representing specified percentage of net sales \| Customer	10	10
Concentration percentage	25.00%	20.00%
Sales Revenue, Net [Member] \| Customer Concentration Risk [Member] \| 10 Largest Alkali Customers [Member]
Revenue, Major Customer [Line Items]
Number of largest customers representing specified percentage of net sales \| Customer	10	10
Concentration percentage	22.00%	25.00%
Sales Revenue, Net [Member] \| Customer Concentration Risk [Member] \| ANSAC [Member]
Revenue, Major Customer [Line Items]
Concentration percentage	13.00%	13.00%

Refers to the number of largest customers representing a specified percentage of net sales of an entity.

No definition available.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6404-108592

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13537-108611

+ Details

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Data Type:	num: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

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
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

No definition available.

+ Details

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

- Definition

Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(a))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

+ Details

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Balance Type:	credit
Period Type:	duration

- Details

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Namespace Prefix:
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Balance Type:
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- Details

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Namespace Prefix:
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Balance Type:
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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

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- Details

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- Details

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- Details

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Namespace Prefix:
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- Details

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Namespace Prefix:
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- Details

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