Number of lease agreements.

No definition available.

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- Definition

Public utilities, cost of debt percentage.

+ References

No definition available.

+ Details

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- Definition

Public utilities number of annual percentage rent breakpoints.

+ References

No definition available.

+ Details

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- Definition

Public utilities number of percentage rent rates.

+ References

No definition available.

+ Details

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- Definition

Public utilities, requested cost of debt percentage, after reduction.

+ References

No definition available.

+ Details

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- Definition

Term of the lessor's leasing arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Percentage of public utility's approved return on equity.

+ References

No definition available.

+ 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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- Definition

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

+ References

No definition available.

+ Details

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Balance Type:	na
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_
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- Definition

The amount for the individual regulatory noncurrent liability as itemized in a table of regulatory noncurrent liabilities as of the end of the period.

+ 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 210.5-02.24)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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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Regulatory Matters - Additional Information (Details) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2016 USD ($) Lease	Sep. 30, 2016 Lease	Dec. 31, 2016 USD ($) Lease RentBreakpoint RentRate	Dec. 31, 2015 USD ($)
Public Utilities General Disclosures [Line Items]
Regulatory Liability \| $	$ 21,004		$ 21,004	$ 10,625
Leasing arrangements, operating leases, term of contract			4 years
Transmission Assets
Public Utilities General Disclosures [Line Items]
Number of annual rent breakpoints \| RentBreakpoint			1
Number of rent rates \| RentRate			1
Distribution Assets
Public Utilities General Disclosures [Line Items]
Number of annual rent breakpoints \| RentBreakpoint			2
Number of rent rates \| RentRate			2
Sharyland Distribution & Transmission Services \| Sharyland
Public Utilities General Disclosures [Line Items]
Number of lease agreements	2	5
Sharyland Distribution & Transmission Services \| Sharyland \| Transmission Assets
Public Utilities General Disclosures [Line Items]
Number of lease agreements			1
Sharyland Distribution & Transmission Services \| Sharyland \| Distribution Assets
Public Utilities General Disclosures [Line Items]
Number of lease agreements			1
Sharyland \| Sharyland Distribution & Transmission Services
Public Utilities General Disclosures [Line Items]
Public utilities, allowed return on equity, percentage			10.00%
Sharyland and SDTS
Public Utilities General Disclosures [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%
Public utilities, reduced cost of debt percentage			4.97%