Additional Available Increase In Borrowing Capacity

No definition available.

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- Definition

Borrowing

+ References

No definition available.

+ Details

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- Definition

Federal Home Loan Bank Borrowing Amount Outstanding

+ References

No definition available.

+ Details

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- Definition

Repayment Of Debt

+ References

No definition available.

+ Details

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- Definition

Unsecured Revolving Credit Facility Additional Borrowing Capacity

+ References

No definition available.

+ Details

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=6584090&loc=d3e28878-108400

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(2))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Amount of debt issuance costs (for example, but not limited to, legal, accounting, broker, and regulatory fees).

+ References

No definition available.

+ Details

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- Definition

Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 325

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6478792&loc=d3e63345-112809

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- Definition

Amount of long-term debt of the registrant maturing in the third fiscal year following the latest fiscal year.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 3

-Subparagraph (SX 210.12-04.(a))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690

+ Details

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- Definition

Amount of long-term debt of the registrant maturing after the fifth fiscal year following the latest fiscal year.

+ References

+ Details

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- Definition

Amount of long-term debt of the registrant maturing in the fifth fiscal year following the latest fiscal year.

+ References

+ Details

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- Definition

Amount of long-term debt of the registrant maturing in the fourth fiscal year following the latest fiscal year.

+ References

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- Definition

Amount of long-term debt of the registrant maturing in the second fiscal year following the latest fiscal year.

+ References

+ Details

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- Definition

Amount of long-term debt of the registrant maturing in the next fiscal year following the latest fiscal year.

+ References

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ 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 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

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- Definition

Amount of cash outflow to acquire Federal Home Loan Bank (FHLB) stock.

+ References

No definition available.

+ Details

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- Definition

The cash inflow from a borrowing with the highest claim on the assets of the entity in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle, if longer).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 14

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3255-108585

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Debt - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	0 Months Ended		12 Months Ended		0 Months Ended	12 Months Ended					0 Months Ended
	May 31, 2013	Dec. 31, 2013	Dec. 31, 2013 CNA Financial [Member]	Dec. 31, 2013 Revolving Credit Agreement [Member] CNA Financial [Member]	Nov. 30, 2013 Diamond Offshore [Member]	Dec. 31, 2013 Diamond Offshore [Member] Revolving Credit Agreement [Member]	Dec. 31, 2013 HighMount [Member]	Dec. 31, 2013 HighMount [Member] Revolving Credit Agreement [Member]	Dec. 31, 2013 Boardwalk Pipeline [Member] Revolving Credit Agreement [Member]	Dec. 31, 2012 Boardwalk Pipeline [Member] Revolving Credit Agreement [Member]	May 31, 2013 2.6% Senior Notes Due 2023 [Member]	May 31, 2013 4.1% Senior Notes Due 2043 [Member]	Nov. 30, 2013 3.5% Senior Notes Due 2023 [Member] Diamond Offshore [Member]	Nov. 30, 2013 4.9% Senior Notes Due 2043 [Member] Diamond Offshore [Member]	Nov. 30, 2013 5.2% Senior Notes Due 2014 [Member] Diamond Offshore [Member]	Nov. 30, 2013 4.9% Senior Notes Due 2015 [Member] Diamond Offshore [Member]
Debt Instrument [Line Items]
Aggregate of long term debt maturing, 2014		$ 840
Aggregate of long term debt maturing, 2015		948
Aggregate of long term debt maturing, 2016		1,500
Aggregate of long term debt maturing, 2017		977
Aggregate of long term debt maturing, 2018		337
Aggregate of long term debt maturing, Thereafter		6,300
Debt instrument principal amount									175	302	500	500	250	750	250	250
Debt instrument interest rate									1.30%		2.60%	4.10%	3.50%	4.90%	5.20%	4.90%
Debt maturity date				Apr. 19, 2016		Sep. 28, 2018		Dec. 01, 2016	Apr. 27, 2017		May 15, 2023	May 15, 2043	Nov. 01, 2023	Nov. 01, 2043	Sep. 01, 2014	Jul. 01, 2015
Net proceeds from issuance of debt instruments	983				988
Underwriters' discounts and commissions and offering expenses on debt	17
Acquisition of FHLBC stock			16
Outstanding borrowings			0
Additional liquidity			330
Revolving credit facility maximum borrowing capacity				250		750		250	1,000
Additional available increase in borrowing capacity				100
Borrowings under credit facility				0		0		0
Available borrowing capacity									825
Repayment of debt							$ 210