Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount of public utility's requested rate increase (decrease) with regulatory agency.

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Percentage of public utility's requested rate increase (decrease) with regulatory agency.

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- Definition

Percentage of the distribution system improvement charge (DSIC) over the base rate. The DSIC allows the Company to add a charge to customers' bills for qualified replacement costs of certain infrastructure without submitting a rate filing as permitted by the regulatory agency.

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Amount of the distribution system improvement charge (DSIC) revenue. The DSIC allows the Company to add a charge to customers' bills for qualified replacement costs of certain infrastructure without submitting a rate filing as permitted by the regulatory agency.

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Increase (decrease) in revenue recorded as a regulatory liability for the difference in calculated current federal income taxes and deferred federal income taxes on accelerated depreciation associated with the Tax Cuts and Jobs Act of 2017, or the 2017 Tax Act.

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Rate Matters (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended		12 Months Ended
Rate Matters (Details) - USD ($) $ in Thousands	May 30, 2018	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Rate Matters [Abstract]
Federal corporate tax rate				21.00%		34.00%
PPUC [Member]
Rate Matters [Abstract]
Revenue recorded as regulatory liability for effects of 2017 Tax Act				$ (983)
Rate Request Filed on May 30, 2018 [Member] \| PPUC [Member] \| Water [Member]
Rate Matters [Abstract]
Requested increase in annual revenue	$ 6,399
Requested percentage increase in annual revenue	13.10%
Rate Request Filed on May 30, 2018 [Member] \| PPUC [Member] \| Wastewater [Member]
Rate Matters [Abstract]
Requested increase in annual revenue	$ 289
Requested percentage increase in annual revenue	25.00%
DSIC [Member] \| PPUC [Member]
Rate Matters [Abstract]
Distribution system improvement charge revenue		$ 436	$ 62	$ 916	$ 62
DSIC [Member] \| PPUC [Member] \| Maximum [Member]
Rate Matters [Abstract]
Distribution system improvement charge percentage over base rate				5.00%
DSIC [Member] \| PPUC [Member] \| Minimum [Member]
Rate Matters [Abstract]
Distribution system improvement charge percentage over base rate				0.00%