Condensed Consolidated Statements of Cash Flows (USD $) In Millions	6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010
Cash flows from operating activities:
Net income	$ 75.2	$ 132.4
Adjustments to reconcile Net income to Net cash provided by operating activities:
Depreciation and amortization	70.2	73.1
Deferred income taxes	37.5	6.4
Unamortized investment tax credit	(1.4)	(1.4)
Charge for early redemption of debt	15.3
Changes in certain assets and liabilities:
Accounts receivable	19.5	4.7
Inventories	(0.3)	(1.8)
Prepaid taxes	(20.7)	(1.0)
Taxes applicable to subsequent years	31.8	29.5
Deferred regulatory costs, net	8.9	4.1
Accounts payable	(5.9)	8.7
Accrued taxes payable	(33.4)	(36.4)
Accrued interest payable	2.0	0.2
Pension, retiree and other benefits	(42.7)	(23.0)
Insurance and claims costs	3.7	(1.5)
Other	25.4	10.9
Net cash provided by operating activities	185.1	204.9
Cash flows from investing activities:
Capital expenditures	(91.4)	(75.1)
Purchase of MC Squared	(8.2)
Purchases of short-term investments and securities	(1.7)	(61.2)
Sales of short-term investments and securities	70.9	14.2
Other	1.8	1.9
Net cash used for investing activities	(28.6)	(120.2)
Cash flows from financing activities:
Dividends paid on common stock	(76.4)	(69.9)
Early redemption of Capital Trust II debt	(122.0)
Premium paid for early redemption of debt	(12.2)
Payment of MC Squared debt	(13.5)
Withdrawals from revolving credit facilities	50.0
Repayments of borrowings from revolving credit facilities	(50.0)
Repurchase of DPL common stock		(3.9)
Exercise of stock options	1.4	1.4
Exercise of warrants	14.7
Tax impact related to exercise of stock options	0.3	0.2
Net cash used for financing activities	(207.7)	(72.2)
Cash and cash equivalents:
Net change	(51.2)	12.5
Balance at beginning of period	124.0	74.9
Cash and cash equivalents at end of period	72.8	87.4
Supplemental cash flow information:
Interest paid, net of amounts capitalized	30.3	35.7
Income taxes paid, net	24.7	53.2
Non-cash financing and investing activities:
Accruals for capital expenditures	22.6	11.3
Long-term liability incurred for purchase of assets	18.7
THE DAYTON POWER AND LIGHT COMPANY [Member]
Cash flows from operating activities:
Net income	83.5	131.5
Adjustments to reconcile Net income to Net cash provided by operating activities:
Depreciation and amortization	66.5	68.0
Deferred income taxes	37.2	5.8
Unamortized investment tax credit	(1.4)	(1.4)
Changes in certain assets and liabilities:
Accounts receivable	25.5	19.9
Inventories		(2.0)
Prepaid taxes	(19.2)	(1.0)
Taxes applicable to subsequent years	31.4	29.4
Deferred regulatory costs, net	8.9	4.1
Accounts payable	(7.8)	7.4
Accrued taxes payable	(32.3)	(37.6)
Accrued interest payable	5.3	(0.1)
Pension, retiree and other benefits	(42.7)	(23.0)
Other	8.3	4.1
Net cash provided by operating activities	163.2	205.1
Cash flows from investing activities:
Capital expenditures	(90.8)	(73.5)
Other	1.7	1.9
Net cash used for investing activities	(89.1)	(71.6)
Cash flows from financing activities:
Dividends paid on common stock	(115.0)	(150.0)
Dividends paid on preferred stock	(0.4)	(0.4)
Withdrawals from revolving credit facilities	50.0
Repayments of borrowings from revolving credit facilities	(50.0)
Net cash used for financing activities	(115.4)	(150.4)
Cash and cash equivalents:
Net change	(41.3)	(16.9)
Balance at beginning of period	54.0	57.1
Cash and cash equivalents at end of period	12.7	40.2
Supplemental cash flow information:
Interest paid, net of amounts capitalized	14.6	19.7
Income taxes paid, net	24.1	53.1
Non-cash financing and investing activities:
Accruals for capital expenditures	22.6	11.3
Long-term liability incurred for purchase of assets	$ 18.7