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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
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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 FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
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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.

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No definition available.

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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 FASB
-Name Accounting Standards Codification
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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 19, 20, 22
-Article 5

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- Definition

The cash outflow for the settlement of long-term borrowing, with the highest claim on the assets of the entity in case of bankruptcy or liquidation, as it matures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- Definition

The cash outflow due to repaying amounts borrowed by issuing commercial paper.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
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Debt - Additional Information (Detail) - USD ($)	1 Months Ended		3 Months Ended
Debt - Additional Information (Detail) - USD ($)	May 31, 2016	Mar. 31, 2016	Mar. 31, 2016	Jun. 30, 2016
Diamond Offshore [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Repayments of commercial paper			$ 287,000,000
Outstanding borrowings				$ 327,000,000
3.8% Senior Notes Due April 1, 2026 [Member]
Debt Instrument [Line Items]
Debt instrument principal amount		$ 500,000,000	$ 500,000,000
Debt instrument interest rate		3.80%	3.80%
Debt maturity date		Apr. 01, 2026
5.3% Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument interest rate		5.30%	5.30%
Repayment of debt		$ 400,000,000
4.5% Senior Notes Due March 1, 2026 [Member] \| CNA Financial [Member]
Debt Instrument [Line Items]
Debt instrument principal amount		$ 500,000,000	$ 500,000,000
Debt instrument interest rate		4.50%	4.50%
Debt maturity date			Mar. 01, 2026
6.5% Senior Notes Due August 15, 2016 [Member] \| CNA Financial [Member]
Debt Instrument [Line Items]
Debt instrument principal amount		$ 350,000,000	$ 350,000,000
Debt instrument interest rate		6.50%	6.50%
Debt maturity date			Aug. 15, 2016
6.0% Senior Notes Due June 1, 2026 [Member] \| Boardwalk Pipeline [Member]
Debt Instrument [Line Items]
Debt instrument principal amount	$ 550,000,000
Debt instrument interest rate	6.00%
Debt maturity date	Jun. 01, 2026