Certain issued and outstanding junior subordinated notes pertaining to certain financial covenants.

No definition available.

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- Definition

Remaining Debt Securities Authorized by the Board

+ References

No definition available.

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- Definition

The board of managers authorized additional debt securities for issuance

+ References

No definition available.

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- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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- 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
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-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- 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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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Topic 470
-SubTopic 20
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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

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- Definition

The portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time.

+ References

No definition available.

+ Details

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Notes and Debentures Narrative (Details) - USD ($) $ in Millions	Dec. 31, 2019	Jul. 31, 2019	May 31, 2019	Dec. 31, 2018	Aug. 31, 2018	Mar. 31, 2018	Mar. 31, 2017
Debt Instrument [Line Items]
Debt	$ 22,839			$ 22,807
Outstanding variable rate debt	0
Debt, fair value	26,648			24,100
Junior Subordinated Debt
Debt Instrument [Line Items]
Subordinated notes related to financial covenants	500
SEC Debt Shelf Registration
Debt Instrument [Line Items]
The board of managers authorized additional debt securities for issuance			$ 2,250				$ 1,500
Remaining amount of debt securities that may be issued	1,675
Mortgage Bonds
Debt Instrument [Line Items]
Debt	$ 81			$ 81
Three Point Fifty Five Percent Debenture Due Feb 15 2050 \| Corporate Debt Securities
Debt Instrument [Line Items]
Debt Instrument issued amount		$ 825
Debt instrument interest rate		3.55%
Four Point One Five Percent Debentures Due December 15, 2048 \| Corporate Debt Securities
Debt Instrument [Line Items]
Debt Instrument issued amount					$ 750
Debt instrument interest rate					4.15%
Four Point Zero Five Percent Debentures Due June 15, 2048 \| Corporate Debt Securities
Debt Instrument [Line Items]
Debt Instrument issued amount						$ 750
Debt instrument interest rate						4.05%
Three Point Two Five Zero Percent Debentures Due June 15, 2027 \| Corporate Debt Securities
Debt Instrument [Line Items]
Debt Instrument issued amount							$ 500
Debt instrument interest rate							3.25%
Four Point One Two Five Percent Debentures Due June 15, 2047 \| Corporate Debt Securities
Debt Instrument [Line Items]
Debt Instrument issued amount							$ 750
Debt instrument interest rate							4.125%