Rate and Regulatory Matters	6 Months Ended
Jun. 30, 2018
Regulated Operations [Abstract]
Rate and Regulatory Matters	Note 2 – Rate and Regulatory Matters Middlesex – In March 2018, Middlesex’s petition to the New Jersey Board of Public Utilities (NJBPU) seeking permission to increase its base water rates was concluded, based on a negotiated settlement, resulting in an increase in annual operating revenues of $5.5 million. In its initial October 2017 filing with the NJBPU, Middlesex had sought an increase of $15.3 million to recover costs for capital infrastructure investments Middlesex has made, or has committed to make, to drinking water infrastructure since the last filing in New Jersey in 2015 as well as increased operations and maintenance costs. During the pendency of this rate matter, the Tax Cuts and Jobs Act of 2017 (the Tax Act) was signed into law. Under the Tax Act the maximum corporate income tax rate was reduced from 35% to 21% effective January 1, 2018. Because income tax is one of the cost components used to determine a regulated utility’s revenue requirement, Middlesex was able to reduce its original rate increase request by $4.9 million to $10.4 million. The new base water rates are designed to recover the increased operating costs as well as a return on invested capital in rate base of $245.5 million, based on an authorized return on equity of 9.6%. As part of the settlement, Middlesex received approval for regulatory accounting treatment of accumulated deferred income tax benefits associated with required adoption of tangible property regulations issued by the Internal Revenue Service (IRS). The settlement agreement allowed for a four-year amortization period for $28.7 million of deferred income tax benefits as well as immediate and prospective recognition of the tangible property regulations tax benefits in future years. The rate increase became effective April 1, 2018. Tidewater - Effective July 1, 2018, Tidewater revised its Delaware Public Service Commission (DEPSC)-approved Distribution System Improvement Charge (DSIC) rate, which is expected to generate $0.2 million of revenues in 2018. A DSIC is a rate-mechanism that allows water utilities to recover investments in, and generate a return on, qualifying capital improvements to their water distribution system made between base rate proceedings. Tax Act - On December 22, 2017, the Tax Act was signed into law making significant changes to the Internal Revenue Code, including a corporate tax rate decrease from 35% to 21% effective for tax years beginning after December 31, 2017. Tariff rates charged to customers in the Company’s regulated companies include recovery of income taxes at the statutory rate in effect at the time those rates became effective. The conclusion of Middlesex’s base rate case and the resulting rates implemented April 1, 2018 reflect the impact of the Tax Act on its revenue requirement. In March 2018, the Company submitted compliance filings with the DEPSC proposing to reduce rates charged to its Delaware customers to reflect the impact of the Tax Act. It is uncertain at this time when the DEPSC will act upon the rate reduction proposals or whether it will accept the proposed methodologies. As of June 30, 2018, the Company has recorded regulatory liabilities of $32.6 million for excess income taxes collected through rates due to the lower income tax rate under the Tax Act. These regulatory liabilities are overwhelmingly related to accelerated tax depreciation deduction timing differences, which are subject to IRS normalization rules. The IRS rules limit how quickly the excess taxes attributable to accelerated tax depreciation can be returned to customers.

Rate and Regulatory Matters

6 Months Ended

Jun. 30, 2018

Note 2 – Rate and Regulatory Matters

Middlesex – In March 2018, Middlesex’s petition to the New Jersey Board of Public Utilities (NJBPU) seeking permission to increase its base water rates was concluded, based on a negotiated settlement, resulting in an increase in annual operating revenues of $5.5 million. In its initial October 2017 filing with the NJBPU, Middlesex had sought an increase of $15.3 million to recover costs for capital infrastructure investments Middlesex has made, or has committed to make, to drinking water infrastructure since the last filing in New Jersey in 2015 as well as increased operations and maintenance costs. During the pendency of this rate matter, the Tax Cuts and Jobs Act of 2017 (the Tax Act) was signed into law. Under the Tax Act the maximum corporate income tax rate was reduced from 35% to 21% effective January 1, 2018. Because income tax is one of the cost components used to determine a regulated utility’s revenue requirement, Middlesex was able to reduce its original rate increase request by $4.9 million to $10.4 million. The new base water rates are designed to recover the increased operating costs as well as a return on invested capital in rate base of $245.5 million, based on an authorized return on equity of 9.6%. As part of the settlement, Middlesex received approval for regulatory accounting treatment of accumulated deferred income tax benefits associated with required adoption of tangible property regulations issued by the Internal Revenue Service (IRS). The settlement agreement allowed for a four-year amortization period for $28.7 million of deferred income tax benefits as well as immediate and prospective recognition of the tangible property regulations tax benefits in future years. The rate increase became effective April 1, 2018.

Tidewater - Effective July 1, 2018, Tidewater revised its Delaware Public Service Commission (DEPSC)-approved Distribution System Improvement Charge (DSIC) rate, which is expected to generate $0.2 million of revenues in 2018. A DSIC is a rate-mechanism that allows water utilities to recover investments in, and generate a return on, qualifying capital improvements to their water distribution system made between base rate proceedings.

Tax Act - On December 22, 2017, the Tax Act was signed into law making significant changes to the Internal Revenue Code, including a corporate tax rate decrease from 35% to 21% effective for tax years beginning after December 31, 2017. Tariff rates charged to customers in the Company’s regulated companies include recovery of income taxes at the statutory rate in effect at the time those rates became effective. The conclusion of Middlesex’s base rate case and the resulting rates implemented April 1, 2018 reflect the impact of the Tax Act on its revenue requirement.

In March 2018, the Company submitted compliance filings with the DEPSC proposing to reduce rates charged to its Delaware customers to reflect the impact of the Tax Act. It is uncertain at this time when the DEPSC will act upon the rate reduction proposals or whether it will accept the proposed methodologies.

As of June 30, 2018, the Company has recorded regulatory liabilities of $32.6 million for excess income taxes collected through rates due to the lower income tax rate under the Tax Act. These regulatory liabilities are overwhelmingly related to accelerated tax depreciation deduction timing differences, which are subject to IRS normalization rules. The IRS rules limit how quickly the excess taxes attributable to accelerated tax depreciation can be returned to customers.