Debt Instrument Maturity Year.

No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399

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-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

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Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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/disclosureRef
-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

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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- Definition

Face (par) amount of the original debt instrument that was repurchased.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

The difference between the reacquisition price and the net carrying amount of the extinguished debt recognized currently as a component of income in the period of extinguishment, net of tax.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114001942&loc=d3e12317-112629

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 4
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-Publisher FASB
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-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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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://fasb.org/us-gaap/role/ref/legacyRef
-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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Debt - Additional Information (Detail) - USD ($) $ in Millions	1 Months Ended	3 Months Ended	6 Months Ended
	May 31, 2019	Mar. 31, 2019	Jun. 30, 2019
CNA Financial [Member] \| Three Point Nine Percentage Notes Due Two Thousand Twenty Nine [Member]
Aggregate principal amount	$ 500
Percentage of senior notes	3.90%
Senior notes due date	May 01, 2029
Debt Instrument, Maturity Date	May 01, 2029
CNA Financial [Member] \| Five Point Nine Percentage Notes Due Two Zero Two Zero [Member]
Percentage of senior notes	5.90%
Senior notes due date	Aug. 15, 2020
Aggregate outstanding principal amount	$ 500
Gain (Loss) on Extinguishment of Debt		$ (21)
Extinguishment of Debt, Gain (Loss), Net of Tax		$ (15)
Debt Instrument, Maturity Date	Aug. 15, 2020
Boardwalk Pipeline [Member] \| Five Point Eight Percentage Notes Due Two Zero One Nine [Member]
Percentage of senior notes	5.80%
Aggregate outstanding principal amount	$ 350
Senior notes due year	2019
Boardwalk Pipeline [Member] \| Four Point Eight Percentage Due Two Thousand Twenty Nine [Member]
Aggregate principal amount	$ 500
Percentage of senior notes	4.80%
Senior notes due date	May 03, 2029
Debt Instrument, Maturity Date	May 03, 2029
Consolidated Container [Member] \| Term Loan [Member]
Senior notes due date			Jun. 14, 2026
Credit agreement term loan			$ 250
Debt Instrument, Description of Variable Rate Basis			London Interbank Offered Rate (“LIBOR”) plus an applicable margin of 3.5%
Debt Instrument, Basis Spread on Variable Rate			3.50%
Debt Instrument, Maturity Date			Jun. 14, 2026