Related Party Transactions (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Related Party Transaction [Line Items]
Sales to related party	$ 6.2	$ 2.4
Charges for Services Provided	36.0	35.8
Net payable to the Service Company	(0.5)	(4.7)
Notes Receivable, Related Parties	35.0	0.0
Investment in trust	0.3	0.3
THE DAYTON POWER AND LIGHT COMPANY [Member]
Related Party Transaction [Line Items]
Sales to related party	6.1	2.3	$ 0.0
Charges for Services Provided	30.9	30.5	0.0
Net payable to the Service Company	(0.5)	(4.7)
Premiums paid for Insurance Services provided by MVIC	(3.2)	(2.9)	(2.9)
Expense recoveries for services provided to DPLER	2.4	2.2	5.2
Note to DPL Capital Trust II Maturing in 2031 - 8.125% [Member]
Related Party Transaction [Line Items]
Note payable to trust	15.6	15.6
Prepayments and Other Current Assets [Member]
Related Party Transaction [Line Items]
Income tax receivable	50.5	16.1
Prepayments and Other Current Assets [Member] \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Related Party Transaction [Line Items]
Income tax receivable	1.5	1.0
DPLER [Member] \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Related Party Transaction [Line Items]
Sales to related party	303.3	487.1	$ 453.9
Deposits received from DPLER	$ 0.0	$ 20.1

Deposits received from DPLER

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Related party expenses, such as employee-related expenses, accounting, information technology, payroll, legal and other administration expenses where the expenses are subsequently charged, at cost, to the related party thereby recovering the expense.

+ References

No definition available.

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Amount for accounts payable to related parties. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount of receivables arising from transactions with related parties due within one year or the normal operating cycle, if longer.

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Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

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For an unclassified balance sheet, amounts due from parties associated with the reporting entity as evidenced by a written promise to pay.

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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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.

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Amount of selling, general and administrative expenses resulting from transactions, excluding transactions that are eliminated in consolidated or combined financial statements, with related party.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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Carrying amount of the liabilities in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the Variable Interest Entity (VIE), where the reporting entity is not the VIE's primary beneficiary.

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