Rates and Other Regulatory Activities	3 Months Ended
Mar. 31, 2018
Regulated Operations [Abstract]
Rates and Other Regulatory Activities	Rates and Other Regulatory Activities Our natural gas and electric distribution operations in Delaware, Maryland and Florida are subject to regulation by their respective PSC; Eastern Shore, our natural gas transmission subsidiary, is subject to regulation by the FERC; and Peninsula Pipeline, our intrastate pipeline subsidiary, is subject to regulation by the Florida PSC. Chesapeake Utilities' Florida natural gas distribution division and FPU’s natural gas and electric distribution operations continue to be subject to regulation, as separate entities, by the Florida PSC. Delaware Effect of the TCJA on ratepayers: As result of the enactment of the TCJA, the Delaware PSC issued an order requiring all rate-regulated utilities to file estimates of the impact of the TCJA on their cost of service for the most recent test year available (including new rate schedules). The order also required utilities to propose procedures for changing rates to reflect those impacts on or before March 31, 2018. Our Delaware Division filed the requisite reports with the Delaware PSC on March 30, 2018. If, after reviewing our report, the Delaware PSC determines to reduce our rates, it will open a new docket and establish a procedural schedule for conducting an evidentiary hearing regarding the impacts of the TCJA on our operations and existing rates. We believe that the ultimate resolution of this matter will not have a material impact on our financial position or results of operations. In addition, on February 1, 2018, the Delaware PSC issued an order requiring Delaware rate-regulated public utilities to accrue regulatory liabilities to reflect the impacts of the Delaware jurisdictional revenue requirement in light of the changes to the federal corporate income tax laws. In compliance with this order, we have established a regulatory liability to reflect the estimated impacts of the changes in the federal corporate income tax rate. Maryland Division and Sandpiper Effect of the TCJA on ratepayers: The Maryland PSC issued an order requiring all Maryland public utilities whose rates are explicitly grossed-up for income taxes to track the impacts of the TCJA beginning January 1, 2018. The order required utilities to: (a) apply regulatory accounting treatment, which includes the use of regulatory assets and liabilities for all impacts of the TCJA; (b) file, on or before February 15, 2018, an explanation of the expected effects of the TCJA on their expenses and revenues; and (c) explain when and how they expect to pass on to their customers the net results of those effects. We established a regulatory liability to reflect the estimated impacts of the changes in the federal corporate income tax rate in compliance with the Maryland PSC’s order. In addition, on February 15, 2018, our Maryland natural gas division and Sandpiper filed preliminary estimates of the annual impact of the change in the statutory federal income tax rate from 35 percent to 21 percent and requested that the Maryland PSC grant us additional time to finalize our calculations. In March 2018, our Maryland natural gas division and Sandpiper supplemented their initial filings to include, among other items, an explanation of when and how they propose to pass the tax impacts on to their customers. In April 2018, the Maryland PSC issued orders directing our Maryland natural gas division and Sandpiper to: (1) file tariff pages reflective of the Maryland PSC's recommended rates with an effective date of May 1, 2018; (2) implement a one-time bill credit for the regulatory liability established for refunds; and, (3) make an informational filing within 60 days after the distribution of the one-time refunds. The orders further directed that, if any additional tax savings are later identified by either our natural gas divisions, we make a filing with the Maryland PSC to return those savings to customers as soon as possible. Florida Florida Electric Reliability/Modernization Pilot Program: In July 2017, FPU’s electric division filed a petition with the Florida PSC, requesting approval to include $15.2 million of certain capital project expenditures in its rate base and to adjust its base rates accordingly. These expenditures are designed to improve the stability and safety of the electric system, while enhancing the capability of FPU’s electrical grid. An interconnection project with FPL, which enables FPU to mitigate fuel costs for its electric customers, was included in the $15.2 million capital project expenditures. In December 2017, the Florida PSC approved this petition, effective January 1, 2018. The settlement agreement prescribed the methodology for adjusting the new rates based on the lower federal income tax rate and the process and methodology regarding the refund of deferred income taxes, reclassified as a regulatory liability, as a result of the TCJA. We have established a regulatory liability to reflect the impacts of the changes in the federal corporate income tax rate in compliance with the settlement agreement. Electric Limited Proceeding-Storm Recovery: In February 2018, FPU’s electric division filed a petition with the Florida PSC, requesting recovery of incremental storm restoration costs related to several hurricanes and tropical storms, along with the replenishment of FPU’s storm reserve to its pre-storm level of $1.5 million. As a result of these hurricanes and tropical storms, FPU’s storm reserve was depleted and is currently at a deficit of $779,000. FPU is requesting approval of a surcharge of $1.82 per kilowatt per hour for two years to recover and replenish storm-related costs. At this time, no date for approval of this petition has been scheduled by the Florida PSC. Effect of the TCJA on ratepayers: The Office of Public Counsel filed a petition requesting that the Florida PSC establish a general docket to investigate and adjust rates for all investor-owned utilities related to the passage of the TCJA. The Florida PSC issued a Memorandum with a recommendation that, if utilities do not agree to a January 1, 2018 effective date, then the effective date should be February 6, 2018. On January 30, 2018, the Florida PSC scheduled informal meetings between its staff and interested persons to discuss the impact of the TCJA. Meetings to discuss the impact for natural gas utilities, electric utilities and water and wastewater utilities were held in mid-February 2018. In December 2017, the Florida PSC issued an order regarding the limited proceeding for FPU's electric division, which prescribes the applicability, timing and treatment of the implications of the TCJA. We established a regulatory liability to reflect the impacts of the changes in the federal corporate income tax rate in compliance with the settlement agreement. We believe that the ultimate resolution of this matter will not have a material impact on our financial position or results of operations. Eastern Shore 2017 Expansion Project: In May 2016, the FERC approved Eastern Shore's request to initiate the pre-filing review process for its 2017 Expansion Project. The 2017 Expansion Project's facilities include approximately 23 miles of pipeline looping in Pennsylvania, Maryland and Delaware; upgrades to existing metering facilities in Lancaster County, Pennsylvania; installation of an additional compressor unit at Eastern Shore’s existing Daleville compressor station in Chester County, Pennsylvania; and approximately 17 miles of new mainline extension and two pressure control stations in Sussex County, Delaware. Eastern Shore entered into precedent agreements with seven existing customers, including three affiliates of Chesapeake Utilities, for a total of 61,162 Dts/d of additional firm natural gas transportation service on Eastern Shore’s pipeline system with an additional 52,500 Dts/d of firm transportation service at certain Eastern Shore receipt facilities. In December 2016, Eastern Shore submitted an application for a CP authorizing construction of the expansion facilities, which the FERC issued in October 2017. The estimated cost of the 2017 Expansion Project is approximately $117.0 million. Eastern Shore submitted its Implementation Plan in October 2017 addressing the actions Eastern Shore will undertake to meet the environmental conditions set forth in the FERC's order. In December 2017, the TETLP interconnect upgrade was placed into service, as Eastern Shore requested. The remaining segments of the 2017 Expansion Project are expected to be placed into service in various phases during the remainder of 2018. 2017 Rate Case Filing: In January 2017, Eastern Shore filed a base rate proceeding with the FERC, as required by the terms of its 2012 rate case settlement agreement. Eastern Shore's proposed rates were based on the mainline cost of service of approximately $60.0 million resulting in an overall requested revenue increase of approximately $18.9 million and a requested rate of return on common equity of 13.75 percent. In March 2017, the FERC issued an order suspending the tariff rates for the usual five-month period. In August 2017, Eastern Shore implemented new rates, subject to refund, based upon the outcome of the rate proceeding. Eastern Shore recorded incremental revenue of approximately $3.7 million for the year ended December 31, 2017, and established a regulatory liability to reserve a portion of the total incremental revenues generated by the new rates until the rate case settlement is approved by the FERC and customers receive refunds according to the terms of the settlement agreement. Eastern Shore filed an uncontested settlement agreement and a motion to place interim settlement rates into effect beginning on January 1, 2018, which interim settlement rates were approved by the FERC in December 2017. The settlement agreement was approved by the FERC in February 2018, and became final in March 2018. Eastern Shore will recover the costs of its 2016 System Reliability Project, along with the cost of investments and expenses associated with various expansion, reliability and safety initiatives. Not considering the effects of the TCJA, base rates will increase, on an annual basis, by approximately $9.8 million. Effect of the TCJA on ratepayers: In March 2018, Eastern Shore filed with the FERC its revised base rates, reflecting the change in its federal corporate income tax rate. These adjusted base rates became effective April 1, 2018 and will generate approximately $6.6 million, on an annual basis. Any excess accumulated deferred income tax balances will flow back to customers over the period determined in the next rate case, absent any transition rule included in the TCJA or other statutes or rules that would govern the flow-back period. In April 2018, Eastern Shore refunded its customers, with interest, the difference between the proposed rates and the settlement rates. The refund to customers also reflected the difference in rates due to the impact of TCJA. In March 2018, the FERC issued a Notice of Proposed Rulemaking proposing a process that will allow it to determine which jurisdictional natural gas pipelines may be collecting unjust and unreasonable rates in light of the recent reduction in the corporate income tax rate in the TCJA and changes to the FERC’s income tax allowance policies following the United Airlines, Inc. v. FERC decision. The Notice of Proposed Rulemaking proposed requiring interstate natural gas pipelines to provide an informational filing to allow the FERC to evaluate the impact of the TCJA on the pipelines’ revenue requirement. In April 2018, Eastern Shore filed comments in this proceeding requesting confirmation that Eastern Shore is not required to provide an informational filing because it has already implemented lower rates based on the 21 percent tax rate in accordance with the settlement agreement in its 2017 rate case approved by the FERC. We believe that the ultimate resolution of this matter will not have a material impact on our financial position or results of operations.

Rates and Other Regulatory Activities

Our natural gas and electric distribution operations in Delaware, Maryland and Florida are subject to regulation by their respective PSC; Eastern Shore, our natural gas transmission subsidiary, is subject to regulation by the FERC; and Peninsula Pipeline, our intrastate pipeline subsidiary, is subject to regulation by the Florida PSC. Chesapeake Utilities' Florida natural gas distribution division and FPU’s natural gas and electric distribution operations continue to be subject to regulation, as separate entities, by the Florida PSC.

Delaware

Effect of the TCJA on ratepayers: As result of the enactment of the TCJA, the Delaware PSC issued an order requiring all rate-regulated utilities to file estimates of the impact of the TCJA on their cost of service for the most recent test year available (including new rate schedules). The order also required utilities to propose procedures for changing rates to reflect those impacts on or before March 31, 2018. Our Delaware Division filed the requisite reports with the Delaware PSC on March 30, 2018. If, after reviewing our report, the Delaware PSC determines to reduce our rates, it will open a new docket and establish a procedural schedule for conducting an evidentiary hearing regarding the impacts of the TCJA on our operations and existing rates. We believe that the ultimate resolution of this matter will not have a material impact on our financial position or results of operations.

In addition, on February 1, 2018, the Delaware PSC issued an order requiring Delaware rate-regulated public utilities to accrue regulatory liabilities to reflect the impacts of the Delaware jurisdictional revenue requirement in light of the changes to the federal corporate income tax laws. In compliance with this order, we have established a regulatory liability to reflect the estimated impacts of the changes in the federal corporate income tax rate.

Maryland Division and Sandpiper

Effect of the TCJA on ratepayers: The Maryland PSC issued an order requiring all Maryland public utilities whose rates are explicitly grossed-up for income taxes to track the impacts of the TCJA beginning January 1, 2018. The order required utilities to: (a) apply regulatory accounting treatment, which includes the use of regulatory assets and liabilities for all impacts of the TCJA; (b) file, on or before February 15, 2018, an explanation of the expected effects of the TCJA on their expenses and revenues; and (c) explain when and how they expect to pass on to their customers the net results of those effects. We established a regulatory liability to reflect the estimated impacts of the changes in the federal corporate income tax rate in compliance with the Maryland PSC’s order. In addition, on February 15, 2018, our Maryland natural gas division and Sandpiper filed preliminary estimates of the annual impact of the change in the statutory federal income tax rate from 35 percent to 21 percent and requested that the Maryland PSC grant us additional time to finalize our calculations. In March 2018, our Maryland natural gas division and Sandpiper supplemented their initial filings to include, among other items, an explanation of when and how they propose to pass the tax impacts on to their customers. In April 2018, the Maryland PSC issued orders directing our Maryland natural gas division and Sandpiper to: (1) file tariff pages reflective of the Maryland PSC's recommended rates with an effective date of May 1, 2018; (2) implement a one-time bill credit for the regulatory liability established for refunds; and, (3) make an informational filing within 60 days after the distribution of the one-time refunds. The orders further directed that, if any additional tax savings are later identified by either our natural gas divisions, we make a filing with the Maryland PSC to return those savings to customers as soon as possible.

Florida

Florida Electric Reliability/Modernization Pilot Program: In July 2017, FPU’s electric division filed a petition with the Florida PSC, requesting approval to include $15.2 million of certain capital project expenditures in its rate base and to adjust its base rates accordingly. These expenditures are designed to improve the stability and safety of the electric system, while enhancing the capability of FPU’s electrical grid. An interconnection project with FPL, which enables FPU to mitigate fuel costs for its electric customers, was included in the $15.2 million capital project expenditures. In December 2017, the Florida PSC approved this petition, effective January 1, 2018. The settlement agreement prescribed the methodology for adjusting the new rates based on the lower federal income tax rate and the process and methodology regarding the refund of deferred income taxes, reclassified as a regulatory liability, as a result of the TCJA. We have established a regulatory liability to reflect the impacts of the changes in the federal corporate income tax rate in compliance with the settlement agreement.

Electric Limited Proceeding-Storm Recovery: In February 2018, FPU’s electric division filed a petition with the Florida PSC, requesting recovery of incremental storm restoration costs related to several hurricanes and tropical storms, along with the replenishment of FPU’s storm reserve to its pre-storm level of $1.5 million. As a result of these hurricanes and tropical storms, FPU’s storm reserve was depleted and is currently at a deficit of $779,000. FPU is requesting approval of a surcharge of $1.82 per kilowatt per hour for two years to recover and replenish storm-related costs. At this time, no date for approval of this petition has been scheduled by the Florida PSC.

Effect of the TCJA on ratepayers: The Office of Public Counsel filed a petition requesting that the Florida PSC establish a general docket to investigate and adjust rates for all investor-owned utilities related to the passage of the TCJA. The Florida PSC issued a Memorandum with a recommendation that, if utilities do not agree to a January 1, 2018 effective date, then the effective date should be February 6, 2018. On January 30, 2018, the Florida PSC scheduled informal meetings between its staff and interested persons to discuss the impact of the TCJA. Meetings to discuss the impact for natural gas utilities, electric utilities and water and wastewater utilities were held in mid-February 2018. In December 2017, the Florida PSC issued an order regarding the limited proceeding for FPU's electric division, which prescribes the applicability, timing and treatment of the implications of the TCJA. We established a regulatory liability to reflect the impacts of the changes in the federal corporate income tax rate in compliance with the settlement agreement. We believe that the ultimate resolution of this matter will not have a material impact on our financial position or results of operations.

Eastern Shore

2017 Expansion Project: In May 2016, the FERC approved Eastern Shore's request to initiate the pre-filing review process for its 2017 Expansion Project. The 2017 Expansion Project's facilities include approximately 23 miles of pipeline looping in Pennsylvania, Maryland and Delaware; upgrades to existing metering facilities in Lancaster County, Pennsylvania; installation of an additional compressor unit at Eastern Shore’s existing Daleville compressor station in Chester County, Pennsylvania; and approximately 17 miles of new mainline extension and two pressure control stations in Sussex County, Delaware. Eastern Shore entered into precedent agreements with seven existing customers, including three affiliates of Chesapeake Utilities, for a total of 61,162 Dts/d of additional firm natural gas transportation service on Eastern Shore’s pipeline system with an additional 52,500 Dts/d of firm transportation service at certain Eastern Shore receipt facilities.

In December 2016, Eastern Shore submitted an application for a CP authorizing construction of the expansion facilities, which the FERC issued in October 2017. The estimated cost of the 2017 Expansion Project is approximately $117.0 million. Eastern Shore submitted its Implementation Plan in October 2017 addressing the actions Eastern Shore will undertake to meet the environmental conditions set forth in the FERC's order.

In December 2017, the TETLP interconnect upgrade was placed into service, as Eastern Shore requested. The remaining segments of the 2017 Expansion Project are expected to be placed into service in various phases during the remainder of 2018.

2017 Rate Case Filing: In January 2017, Eastern Shore filed a base rate proceeding with the FERC, as required by the terms of its 2012 rate case settlement agreement. Eastern Shore's proposed rates were based on the mainline cost of service of approximately $60.0 million resulting in an overall requested revenue increase of approximately $18.9 million and a requested rate of return on common equity of 13.75 percent. In March 2017, the FERC issued an order suspending the tariff rates for the usual five-month period.

In August 2017, Eastern Shore implemented new rates, subject to refund, based upon the outcome of the rate proceeding. Eastern Shore recorded incremental revenue of approximately $3.7 million for the year ended December 31, 2017, and established a regulatory liability to reserve a portion of the total incremental revenues generated by the new rates until the rate case settlement is approved by the FERC and customers receive refunds according to the terms of the settlement agreement. Eastern Shore filed an uncontested settlement agreement and a motion to place interim settlement rates into effect beginning on January 1, 2018, which interim settlement rates were approved by the FERC in December 2017. The settlement agreement was approved by the FERC in February 2018, and became final in March 2018. Eastern Shore will recover the costs of its 2016 System Reliability Project, along with the cost of investments and expenses associated with various expansion, reliability and safety initiatives. Not considering the effects of the TCJA, base rates will increase, on an annual basis, by approximately $9.8 million.

Effect of the TCJA on ratepayers: In March 2018, Eastern Shore filed with the FERC its revised base rates, reflecting the change in its federal corporate income tax rate. These adjusted base rates became effective April 1, 2018 and will generate approximately $6.6 million, on an annual basis. Any excess accumulated deferred income tax balances will flow back to customers over the period determined in the next rate case, absent any transition rule included in the TCJA or other statutes or rules that would govern the flow-back period. In April 2018, Eastern Shore refunded its customers, with interest, the difference between the proposed rates and the settlement rates. The refund to customers also reflected the difference in rates due to the impact of TCJA.

In March 2018, the FERC issued a Notice of Proposed Rulemaking proposing a process that will allow it to determine which jurisdictional natural gas pipelines may be collecting unjust and unreasonable rates in light of the recent reduction in the corporate income tax rate in the TCJA and changes to the FERC’s income tax allowance policies following the United Airlines, Inc. v. FERC decision. The Notice of Proposed Rulemaking proposed requiring interstate natural gas pipelines to provide an informational filing to allow the FERC to evaluate the impact of the TCJA on the pipelines’ revenue requirement. In April 2018, Eastern Shore filed comments in this proceeding requesting confirmation that Eastern Shore is not required to provide an informational filing because it has already implemented lower rates based on the 21 percent tax rate in accordance with the settlement agreement in its 2017 rate case approved by the FERC. We believe that the ultimate resolution of this matter will not have a material impact on our financial position or results of operations.