General partner interest.

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- Definition

Increase Decrease In Accumulated Other Comprehensive Income Loss

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No definition available.

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- Definition

Proceeds From Subsidiary Public Offering

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No definition available.

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- Definition

Amount of other increase (decrease) in additional paid in capital (APIC).

+ References

No definition available.

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- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.29)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 30

-Article 5

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- Definition

This element represents the aggregate cost of investments accounted for under the equity method of accounting.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.12)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 12

-Article 5

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- Definition

The cash inflow from parent as a source of financing that is recorded as additional paid in capital.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 14

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

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- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

+ Details

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- Definition

Percentage of subsidiary's or equity method investee's stock owned by parent immediately after all stock transactions.

+ References

No definition available.

+ Details

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- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

+ References

+ Details

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- Definition

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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-Name Accounting Standards Codification

-Topic 505

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-Section 50

-Paragraph 2

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

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-Topic 505

-SubTopic 30

-Section 45

-Paragraph 1

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Shareholders' Equity - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	1 Months Ended	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Shareholders Equity [Line Items]
Increase (decrease) in Additional paid-in capital	$ (2)
Common stock, shares issued	373,194,344us-gaap_CommonStockSharesIssued	373,194,344us-gaap_CommonStockSharesIssued		372,934,540us-gaap_CommonStockSharesIssued
Increase in accumulated other comprehensive income	1	1
Treasury stock repurchased, shares		1,800,000us-gaap_TreasuryStockSharesAcquired	500,000us-gaap_TreasuryStockSharesAcquired
Purchase of Loews treasury stock		71	24
Diamond Offshore [Member]
Shareholders Equity [Line Items]
Purchase of common stock		900,000
Common stock, aggregate cost	24	24
Increase (decrease) in Additional paid-in capital		3
Diamond Offshore [Member] \| Minimum [Member]
Shareholders Equity [Line Items]
Subsidiary ownership percentage		52.50%
Diamond Offshore [Member] \| Maximum [Member]
Shareholders Equity [Line Items]
Subsidiary ownership percentage		53.10%
Boardwalk Pipeline [Member]
Shareholders Equity [Line Items]
Common stock, shares issued	6,700,000	6,700,000
Proceeds from subsidiary public offering	109
Contribution from the company	$ 2
General partner interest	2.00%	2.00%
Boardwalk Pipeline [Member] \| Minimum [Member]
Shareholders Equity [Line Items]
Subsidiary ownership percentage	51.00%
Boardwalk Pipeline [Member] \| Maximum [Member]
Shareholders Equity [Line Items]
Subsidiary ownership percentage	53.00%