Summary of Significant Accounting Policies (Tables)

6 Months Ended

Jun. 30, 2020

Related Party Transaction [Line Items]

New Accounting Pronouncements, Policy [Policy Text Block]

New accounting pronouncements adopted in 2020 – The following table provides a brief description of recently adopted accounting pronouncements that had an impact on our consolidated financial statements. Accounting pronouncements not listed below were assessed and determined to be either not applicable or did not have a material impact on our consolidated financial statements.

ASU Number and Name	Description	Date of Adoption	Effect on the financial statements upon adoption
2016-13, 2018-19, 2019-04, 2019-05, 2019-10, 2019-11, 2020-02, 2020-03 Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments	See discussion of the ASU below.	January 1, 2020	See impact upon adoption of the standard below.

On January 1, 2020, we adopted ASC 326 Financial Instruments - Credit Losses and its subsequent corresponding updates ("ASC 326"). The new standard updates the impairment model for financial assets measured at amortized cost, known as the Current Expected Credit Loss ("CECL") model. For trade and other receivables, held-to-maturity debt securities, loans and other instruments, entities are required to use a new forward-looking "expected loss" model that generally results in the earlier recognition of an allowance for credit losses. For available-for-sale debt securities with unrealized losses, entities measure credit losses as it was done under previous GAAP, except that unrealized losses due to credit-related factors are now recognized as an allowance on the balance sheet with a corresponding adjustment to earnings in the income statement.

We applied the modified retrospective method of adoption for ASC 326. Under this transition method, we applied the transition provisions starting at the date of adoption. The new current expected credit loss model primarily impacts the calculation of expected credit losses on our trade accounts receivable. The adoption of ASC 326 and application

of CECL on our trade accounts receivable did not have a material impact on our condensed consolidated financial statements.

New Accounting Pronouncements Issued But Not Yet Effective – The following table provides a brief description of recent accounting pronouncements that could have a material impact on our consolidated financial statements. Accounting pronouncements not listed below were assessed and determined to be either not applicable or are expected to have no material impact on our consolidated financial statements.

ASU Number and Name	Description	Date of Adoption	Effect on the financial statements upon adoption
2020-04, Reference Rate Form (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting	The standard provides optional expedients and exceptions for applying GAAP to contracts, hedging relationships and other transactions that reference to LIBOR or another reference rate expected to be discontinued by reference rate reform. This standard is effective for a limited period of time (March 12, 2020 - December 21, 2022).	Effective for all entities March 12, 2020 - December 31, 2022	We are currently evaluating the impact of adopting the standard on our condensed consolidated financial statements.
2019-12, Income Taxes (Topic 740): Simplifying the Accounting For Income Taxes	The standard removes certain exceptions for recognizing deferred taxes for investments, performing intraperiod allocation and calculating income taxes in interim periods. It also adds guidance to reduce complexity in certain areas, including recognizing deferred taxes for tax goodwill and allocating taxes to members of a consolidated group. Transition method: various	January 1, 2021. Early adoption is permitted.	We are currently evaluating the impact of adopting the standard on our condensed consolidated financial statements.

Schedule of Cash and Cash Equivalents [Table Text Block]

The following table provides a summary of cash, cash equivalents, and restricted cash amounts reported on the Condensed Consolidated Balance Sheets that reconcile to the total of such amounts as shown on the Condensed Consolidated Statements of Cash Flows:

$ in millions	June 30, 2020		December 31, 2019
Cash and cash equivalents	$	412.2	$	36.5
Restricted cash	0.1		10.5
Cash, Cash Equivalents, and Restricted Cash, End of Period	$	412.3	$	47.0

Schedule of New Accounting Pronouncements

– The following table provides a brief description of recently adopted accounting pronouncements that had an impact on our consolidated financial statements. Accounting pronouncements not listed below were assessed and determined to be either not applicable or did not have a material impact on our consolidated financial statements.

ASU Number and Name	Description	Date of Adoption	Effect on the financial statements upon adoption
2016-13, 2018-19, 2019-04, 2019-05, 2019-10, 2019-11, 2020-02, 2020-03 Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments	See discussion of the ASU below.	January 1, 2020	See impact upon adoption of the standard below.

On January 1, 2020, we adopted ASC 326 Financial Instruments - Credit Losses and its subsequent corresponding updates ("ASC 326"). The new standard updates the impairment model for financial assets measured at amortized cost, known as the Current Expected Credit Loss ("CECL") model. For trade and other receivables, held-to-maturity debt securities, loans and other instruments, entities are required to use a new forward-looking "expected loss" model that generally results in the earlier recognition of an allowance for credit losses. For available-for-sale debt securities with unrealized losses, entities measure credit losses as it was done under previous GAAP, except that unrealized losses due to credit-related factors are now recognized as an allowance on the balance sheet with a corresponding adjustment to earnings in the income statement.

We applied the modified retrospective method of adoption for ASC 326. Under this transition method, we applied the transition provisions starting at the date of adoption. The new current expected credit loss model primarily impacts the calculation of expected credit losses on our trade accounts receivable. The adoption of ASC 326 and application

of CECL on our trade accounts receivable did not have a material impact on our condensed consolidated financial statements.

New Accounting Pronouncements Issued But Not Yet Effective – The following table provides a brief description of recent accounting pronouncements that could have a material impact on our consolidated financial statements. Accounting pronouncements not listed below were assessed and determined to be either not applicable or are expected to have no material impact on our consolidated financial statements.

ASU Number and Name	Description	Date of Adoption	Effect on the financial statements upon adoption
2020-04, Reference Rate Form (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting	The standard provides optional expedients and exceptions for applying GAAP to contracts, hedging relationships and other transactions that reference to LIBOR or another reference rate expected to be discontinued by reference rate reform. This standard is effective for a limited period of time (March 12, 2020 - December 21, 2022).	Effective for all entities March 12, 2020 - December 31, 2022	We are currently evaluating the impact of adopting the standard on our condensed consolidated financial statements.
2019-12, Income Taxes (Topic 740): Simplifying the Accounting For Income Taxes	The standard removes certain exceptions for recognizing deferred taxes for investments, performing intraperiod allocation and calculating income taxes in interim periods. It also adds guidance to reduce complexity in certain areas, including recognizing deferred taxes for tax goodwill and allocating taxes to members of a consolidated group. Transition method: various	January 1, 2021. Early adoption is permitted.	We are currently evaluating the impact of adopting the standard on our condensed consolidated financial statements.

THE DAYTON POWER AND LIGHT COMPANY [Member]

Related Party Transaction [Line Items]

New Accounting Pronouncements, Policy [Policy Text Block]

New accounting pronouncements adopted in 2020 – The following table provides a brief description of recently adopted accounting pronouncements that had an impact on our financial statements. Accounting pronouncements not listed below were assessed and determined to be either not applicable or did not have a material impact on our financial statements.

ASU Number and Name	Description	Date of Adoption	Effect on the financial statements upon adoption
2016-13, 2018-19, 2019-04, 2019-05, 2019-10, 2019-11, 2020-02, 2020-03 Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments	See discussion of the ASU below.	January 1, 2020	See impact upon adoption of the standard below.

On January 1, 2020, we adopted ASC 326 Financial Instruments - Credit Losses and its subsequent corresponding updates ("ASC 326"). The new standard updates the impairment model for financial assets measured at amortized cost, known as the Current Expected Credit Loss ("CECL") model. For trade and other receivables, held-to-maturity debt securities, loans and other instruments, entities are required to use a new forward-looking "expected loss" model that generally results in the earlier recognition of an allowance for credit losses. For available-for-sale debt securities with unrealized losses, entities measure credit losses as it was done under previous GAAP, except that unrealized losses due to credit-related factors are now recognized as an allowance on the balance sheet with a corresponding adjustment to earnings in the income statement.

We applied the modified retrospective method of adoption for ASC 326. Under this transition method, we applied the transition provisions starting at the date of adoption. The new current expected credit loss model primarily impacts the calculation of expected credit losses on our trade accounts receivable. The adoption of ASC 326 and application of CECL on our trade accounts receivable did not have a material impact on our condensed financial statements.

New Accounting Pronouncements Issued But Not Yet Effective – The following table provides a brief description of recent accounting pronouncements that could have a material impact on our financial statements. Accounting pronouncements not listed below were assessed and determined to be either not applicable or are expected to have no material impact on our financial statements.

ASU Number and Name	Description	Date of Adoption	Effect on the financial statements upon adoption
2020-04, Reference Rate Form (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting	The standard provides optional expedients and exceptions for applying GAAP to contracts, hedging relationships and other transactions that reference to LIBOR or another reference rate expected to be discontinued by reference rate reform. This standard is effective for a limited period of time (March 12, 2020 - December 21, 2022).	Effective for all entities March 12, 2020 - December 31, 2022	We are currently evaluating the impact of adopting the standard on our condensed financial statements.

ASU Number and Name	Description	Date of Adoption	Effect on the financial statements upon adoption
2019-12, Income Taxes (Topic 740): Simplifying the Accounting For Income Taxes	The standard removes certain exceptions for recognizing deferred taxes for investments, performing intraperiod allocation and calculating income taxes in interim periods. It also adds guidance to reduce complexity in certain areas, including recognizing deferred taxes for tax goodwill and allocating taxes to members of a consolidated group. Transition method: various	January 1, 2021. Early adoption is permitted.	We are currently evaluating the impact of adopting the standard on our condensed financial statements.

Schedule of Cash and Cash Equivalents [Table Text Block]

The following table provides a summary of cash, cash equivalents, and restricted cash amounts reported on the Condensed Balance Sheets that reconcile to the total of such amounts as shown on the Condensed Statements of Cash Flows:

$ in millions	June 30, 2020		December 31, 2019
Cash and cash equivalents	$	74.1	$	10.8
Restricted cash	0.1		10.5
Cash, Cash Equivalents, and Restricted Cash, End of Period	$	74.2	$	21.3