Name:	ck91882_ScheduleOfAmountsInRegulatoryAssetsToBeRecognizedOverTheNextFiscalYearTableTextBlock
Namespace Prefix:	ck91882_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

Tabular disclosure of the assumptions used to determine for pension plans and/or other employee benefit plans the net benefit cost, including assumed discount rates, rate increase in compensation increase and expected long-term rates of return on plan assets.

No definition available.

Name:	ck91882_ScheduleOfAssumptionsUsedInDeterminingNetPeriodicBenefitCostTableTextBlock
Namespace Prefix:	ck91882_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

Tabular disclosure of the assumptions used to determine for pension plans and/or other employee benefit plans the benefit obligation, including assumed discount rates, rate increase in compensation increase, and expected long-term rates of return on plan assets.

No definition available.

Name:	ck91882_ScheduleOfAssumptionsUsedToDetermineBenefitObligationsTableTextBlock
Namespace Prefix:	ck91882_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

Tabular disclosure of the amount recognized in accumulated other comprehensive income.

No definition available.

Name:	ck91882_ScheduleOfDefinedBenefitPlanAmountsRecognizedInAccumulatedOtherComprehensiveIncomeLossTableTextBlock
Namespace Prefix:	ck91882_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

Schedule of defined benefit plan, amounts recognized in regulatory assets [Table Text Block].

No definition available.

Name:	ck91882_ScheduleOfDefinedBenefitPlanAmountsRecognizedInRegulatoryAssetsTableTextBlock
Namespace Prefix:	ck91882_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

Schedule of defined benefit plan, Other changes in plan assets recognized in regulatory assets [Table Text Block].

No definition available.

Name:	ck91882_ScheduleOfDefinedBenefitPlanOtherChangesInPlanAssetsRecognizedInRegulatoryAssetsTableTextBlock
Namespace Prefix:	ck91882_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

Disclosure of the fair value of defined benefit plan assets by the level within the fair value hierarchy in which the fair value measurements fall, segregating fair value measurements using quoted prices in active markets for identical assets or liabilities (level 1), significant other observable inputs (level 2), and significant unobservable inputs (level 3).

No definition available.

Name:	ck91882_ScheduleOfFairValueOfPlanAssetsByMeasurementLevelsTableTextBlock
Namespace Prefix:	ck91882_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

Name:	us-gaap_CompensationAndRetirementDisclosureAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Tabular disclosure of the major categories of plan assets of pension plans and/or other employee benefit plans. This information may include, but is not limited to, the target allocation of plan assets, the fair value of each major category of plan assets, and the level within the fair value hierarchy in which the fair value measurements fall.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(5)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

Name:	us-gaap_ScheduleOfAllocationOfPlanAssetsTableTextBlock
Namespace Prefix:	us-gaap_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

Tabular disclosure of the amounts that are recognized in the balance sheet (or statement of financial position) for pension plans and/or other employee benefit plans, showing separately the assets and current and noncurrent liabilities (if applicable) recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

Name:	us-gaap_ScheduleOfAmountsRecognizedInBalanceSheetTableTextBlock
Namespace Prefix:	us-gaap_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

Tabular disclosure of the reconciliation of beginning and ending balances of the fair value of plan assets of pension plans and/or other employee benefit plans showing separately, if applicable, the effects during the period attributable to each of the following: actual return on plan assets, foreign currency exchange rate changes, contributions by the employer, contributions by plan participants, benefits paid, business combinations, divestitures, and settlements.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

Name:	us-gaap_ScheduleOfChangesInFairValueOfPlanAssetsTableTextBlock
Namespace Prefix:	us-gaap_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

Tabular disclosure of the change in the benefit obligation of pension plans and/or other employee benefit plans from the beginning to the end of the period, showing separately, if applicable, the effects of the following: service cost, interest cost, contributions by plan participants, actuarial gains and losses, foreign currency exchange rate changes, benefits paid, plan amendments, business combinations, divestitures, curtailments, settlements, and special and contractual termination benefits.

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

Name:	us-gaap_ScheduleOfChangesInProjectedBenefitObligationsTableTextBlock
Namespace Prefix:	us-gaap_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

Tabular disclosure of the changes in plan assets and benefit obligations recognized in other comprehensive income (loss) during the period.

No definition available.

Name:	us-gaap_ScheduleOfDefinedBenefitPlanAmountsRecognizedInOtherComprehensiveIncomeLossTableTextBlock
Namespace Prefix:	us-gaap_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

Tabular disclosure of benefits expected to be paid by pension plans and/or other employee benefit plans in each of the next five fiscal years and in the aggregate for the five fiscal years thereafter.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

Name:	us-gaap_ScheduleOfExpectedBenefitPaymentsTableTextBlock
Namespace Prefix:	us-gaap_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

Tabular disclosure of the components of net benefit costs for pension plans and/or other employee benefit plans including service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) recognized due to settlements or curtailments.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

Name:	us-gaap_ScheduleOfNetBenefitCostsTableTextBlock
Namespace Prefix:	us-gaap_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

Tabular disclosure of net funded status of pension plans and/or other employee benefit plans.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920