Public utilities, cost of debt percentage.

No definition available.

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Period Type:	duration

- Definition

Percentage of public utility's approved return on equity.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Period end amount of property, plant and equipment (PPE) related to utility distribution.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Any changes made to the basis costs of intangible utility plants.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.13(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Period Type:	instant

- Definition

Period end amount of property, plant and equipment (PPE) related to utility transmission owned by public utility.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	debit
Period Type:	instant

- Definition

Percentage of public utility's requested debt to capital, including debt and equity.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
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Period Type:	duration

- Definition

Percentage of public utility's requested equity to capital, including debt and equity.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Subsequent Events - Additional Information (Details) - USD ($) $ in Thousands	Jul. 21, 2017	Jun. 30, 2017	Dec. 31, 2016
Subsequent Event [Line Items]
Distribution assets		$ 614,174	$ 575,648
Transmission assets		$ 1,236,848	$ 1,203,164
Sharyland Distribution & Transmission Services \| Subsequent Event \| Definitive Agreement \| Oncor Electric Delivery Company LLC
Subsequent Event [Line Items]
Distribution assets	$ 400,000
Customary adjustments made in cash	20,000
Sharyland Distribution & Transmission Services \| Subsequent Event \| Definitive Agreement \| Oncor Electric Delivery Company LLC \| West and Central Texas
Subsequent Event [Line Items]
Transmission assets	$ 380,000
Sharyland \| Sharyland Distribution & Transmission Services \| Subsequent Event
Subsequent Event [Line Items]
Public utilities, allowed return on equity, percentage	9.70%
Sharyland and SDTS \| Subsequent Event
Subsequent Event [Line Items]
Public utilities, requested capital structure, debt percentage	55.00%
Public utilities, requested capital structure, equity percentage	45.00%
Public utilities cost of debt percentage	6.73%