Consolidated Statement of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Operating Activities
Net Income	$ 161.6	$ 185.5	$ 174.1
AFUDC – Equity	(1.9)	(2.3)	(1.2)
Income from Equity Investments – Net of Dividends	(3.2)	(5.6)	(2.3)
Change in Fair Value of Contingent Consideration	0.0	0.0	(2.0)
Realized and Unrealized (Gain) / Loss on Investments and Property, Plant and Equipment	(1.3)	(1.6)	2.7
Depreciation Expense	217.7	200.6	200.1
Amortization of PSAs	(11.3)	(11.6)	(23.6)
Amortization of Other Intangible Assets and Other Assets	10.4	11.7	9.6
Deferred Income Tax Benefit	(39.5)	(6.7)	(15.8)
Share-Based and ESOP Compensation Expense	6.1	6.3	6.8
Defined Benefit Pension and Other Postretirement Benefit Expense	0.1	1.2	8.6
Bad Debt Expense	2.7	(0.1)	1.1
Provision (Payments) for Interim Rate Refund	0.0	(40.0)	16.3
Provision (Payments) for Tax Reform Refund	(0.2)	(10.4)	10.7
Gain on Sale of U.S. Water Services	0.0	(23.6)	0.0
Changes in Operating Assets and Liabilities
Accounts Receivable	(18.2)	22.6	(10.7)
Inventories	(1.4)	(4.1)	55.5
Prepayments and Other	0.9	0.3	(4.0)
Accounts Payable	11.8	(8.8)	13.6
Other Current Liabilities	16.7	(13.7)	6.7
Cash Contributions to Defined Benefit Pension Plans	(10.7)	(10.4)	(15.0)
Changes in Regulatory and Other Non-Current Assets	(31.0)	(25.2)	5.0
Changes in Regulatory and Other Non-Current Liabilities	(9.5)	(17.2)	(4.9)
Cash from Operating Activities	299.8	246.9	431.3
Investing Activities
Proceeds from Sale of Available-for-sale Securities	12.8	12.1	10.2
Payments for Purchase of Available-for-sale Securities	(8.7)	(12.2)	(13.3)
Payments for Equity Investments	(99.1)	(37.9)	(39.2)
Return of Capital from Equity Investments	0.0	8.3	0.0
Additions to Property, Plant and Equipment	(717.8)	(597.1)	(312.4)
Proceeds from Sale of U.S. Water Services - Net of Transaction Costs and Cash Retained	0.0	268.6	0.0
Other Investing Activities	0.0	15.5	7.5
Cash for Investing Activities	(812.8)	(342.7)	(347.2)
Financing Activities
Proceeds from Issuance of Common Stock	18.1	1.9	20.3
Proceeds from Issuance of Long-Term Debt	672.4	201.9	75.6
Repayments of Long-Term Debt	(488.6)	(72.2)	(95.5)
Proceeds from Non-Controlling Interest in Subsidiaries - Net of Issuance Costs	414.5	103.8	0.0
Acquisition-Related Contingent Consideration Payments	0.0	(3.8)	0.0
Dividends on Common Stock	(128.2)	(121.4)	(115.0)
Other Financing Activities	(2.5)	(0.9)	(0.6)
Cash (for) from Financing Activities	485.7	109.3	(115.2)
Change in Cash, Cash Equivalents and Restricted Cash	(27.3)	13.5	(31.1)
Cash, Cash Equivalents and Restricted Cash	$ 65.2	$ 92.5	$ 79.0