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AAO associated with MGP costs incurred requested amount, cap

No definition available.

Name:	ogs_AAOassociatedwithMGPcostsrequestedamountcap
Namespace Prefix:	ogs_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

[Line Items] for Disclosure of commitments and contingencies [Table]

No definition available.

Name:	ogs_CommitmentsandContingenciesLineItems
Namespace Prefix:	ogs_
Data Type:	xbrli:stringItemType
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Potential costs associated with environmental remediation, high-end range.

No definition available.

Name:	ogs_EnvironmentalReserveEstimateRangeHigh
Namespace Prefix:	ogs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Potential costs associated with environmental remediation, low-end range.

No definition available.

Name:	ogs_EnvironmentalReserveEstimateRangeLow
Namespace Prefix:	ogs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Number of former manufactured gas sites where we own or retain legal responsibility.

No definition available.

Name:	ogs_NumberOfFormerManufacturedGasSitesWhereWeOwnOrRetainLegalResponsibilityForEnvironmentalConditions
Namespace Prefix:	ogs_
Data Type:	xbrli:integerItemType
Balance Type:	na
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Number of sites where regulatory closure has been achieved

No definition available.

Name:	ogs_NumberOfSitesWhereRegulatoryClosureHasBeenAchieved
Namespace Prefix:	ogs_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

Number of sites where groundwater continues to be monitored in accordance to plans approved by the KDHE.

No definition available.

Name:	ogs_Numberofsiteswithongoinggroundwatermonitoring
Namespace Prefix:	ogs_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

Minimum percentage yield required to test pipelines previously untested in high-consequence areas.

No definition available.

Name:	ogs_Percentageyieldofhighconsequencepipelineareas
Namespace Prefix:	ogs_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Amount of expense (reversal of expense) which increases (decreases) the accrual for environmental loss contingencies from revisions in estimates to existing obligations. Excludes changes related to business acquisitions, divestitures, or currency movement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 5.Y.Q2)
-URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751