Defined benefit plan cost of providing special or contractual termination benefit recognized during period net of tax.

No definition available.

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Balance Type:	debit
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- Definition

Defined benefit plan, expected future employer contributions, remainder of fiscal year, description.

+ References

No definition available.

+ Details

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- Definition

Amount of payment, which decreases benefit obligation of defined benefit plan, for irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Transaction constituting settlement includes, but is not limited to, making lump-sum cash payment to participant in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contract. Excludes decreases to benefit obligation for remeasurement due to settlement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)(10)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

+ Details

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Period Type:	duration

- Definition

Amount of cost of providing special or contractual termination benefits payable from defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (q)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

+ Details

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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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- Details

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Employee Benefit Plans (Narrative) (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Sep. 30, 2020
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, expected future employer contributions, next fiscal year, description			No
Voluntary retirement program related charges		$ 62
Voluntary retirement program related charges net of taxes		47
Other Operations and Maintenance Expense
Defined Benefit Plan Disclosure [Line Items]
Voluntary retirement program related charges		50
Other Taxes
Defined Benefit Plan Disclosure [Line Items]
Voluntary retirement program related charges		3
Other Income (Expense), Net
Defined Benefit Plan Disclosure [Line Items]
Voluntary retirement program related charges		$ 9
Settlement losses as a result of voluntary retirement program	$ 11