Amount capitalized into regulatory assets due to actions of regulator related to pension benefits

No definition available.

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- Definition

The total amount of net periodic benefit cost actuarilly determined for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

+ References

No definition available.

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- Definition

Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan.

+ References

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- Definition

Amount of prior service cost (credit) recognized in net periodic benefit cost (credit) of defined benefit plan.

+ References

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- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(5)(ii)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2709-114920

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(5)(iv)(01)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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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.

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- Definition

Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan.

+ References

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- Definition

Amount of cost recognized for passage of time related to defined benefit plan.

+ References

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- Definition

Amount of net periodic benefit cost (credit) for defined benefit plan.

+ References

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- Definition

Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

+ References

+ Details

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- Details

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Benefit Plans Components of Net Periodic Benefit Cost (Details) - USD ($)	3 Months Ended		6 Months Ended			12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Sep. 30, 2018	Mar. 31, 2018	Mar. 31, 2017	Sep. 30, 2018	Sep. 30, 2017
Other Pension Plan
Retirement Plan Disclosure
Defined benefit plan contributions				$ 150,000,000			$ 800,000,000
Pension Benefits
Retirement Plan Disclosure
Service cost	$ 13,000,000	$ 13,000,000		27,000,000	$ 30,000,000
Interest cost	119,000,000	116,000,000		237,000,000	232,000,000
Expected return on plan assets	(119,000,000)	(114,000,000)		(239,000,000)	(228,000,000)
Amortization of prior service cost	(24,000,000)	(24,000,000)		(49,000,000)	(49,000,000)
Recognized net actuarial loss	101,000,000	120,000,000		204,000,000	236,000,000
Total net periodic benefit cost as actuarially determined	90,000,000	111,000,000		180,000,000	221,000,000
Amount capitalized due to actions of regulator	(13,000,000)	(34,000,000)		(27,000,000)	(68,000,000)
Total net periodic benefit cost	77,000,000	77,000,000		153,000,000	153,000,000
Other Post-retirement Benefits
Retirement Plan Disclosure
Defined benefit plan contributions				9,000,000	17,000,000
Service cost	3,000,000	5,000,000		7,000,000	9,000,000
Interest cost	4,000,000	4,000,000		9,000,000	11,000,000
Expected return on plan assets	0	0		0	0
Amortization of prior service cost	(5,000,000)	(10,000,000)		(11,000,000)	(11,000,000)
Recognized net actuarial loss	2,000,000	5,000,000		4,000,000	7,000,000
Total net periodic benefit cost as actuarially determined	4,000,000	4,000,000		9,000,000	16,000,000
Amount capitalized due to actions of regulator	0	0		0	0
Total net periodic benefit cost	$ 4,000,000	$ 4,000,000		$ 9,000,000	$ 16,000,000
Scenario, Forecast \| Other Pension Plan
Retirement Plan Disclosure
Defined benefit plan contributions			$ 150,000,000			$ 300,000,000