Consolidated Balance Sheet - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Current Assets [Abstract]
Cash and Cash Equivalents	$ 353.3	$ 69.1
Accounts Receivable (Less Allowance of $1.0 and $1.7)	98.9	144.4
Inventories – Net	73.8	86.7
Prepayments and Other	30.4	34.1
Total Current Assets	556.4	334.3
Property, Plant and Equipment – Net	3,940.5	3,904.4
Regulatory Assets	385.1	389.5
Equity Investments	154.8	161.1
Goodwill and Intangible Assets – Net	1.1	223.3
Other Non-Current Assets	180.9	152.4
Total Assets	5,218.8	5,165.0
Current Liabilities [Abstract]
Accounts Payable	134.4	149.8
Accrued Taxes	60.3	51.4
Accrued Interest	14.9	17.9
Long-Term Debt Due Within One Year	14.3	57.5
Other	98.5	128.5
Total Current Liabilities	322.4	405.1
Long-Term Debt	1,525.0	1,428.5
Deferred Income Taxes	215.5	223.6
Regulatory Liabilities	504.1	512.1
Defined Benefit Pension and Other Postretirement Benefit Plans	165.2	177.3
Other Non-Current Liabilities	287.9	262.6
Total Liabilities	3,020.1	3,009.2
Commitments, Guarantees and Contingencies (Note 7)
Shareholders’ Equity [Abstract]
Common Stock Without Par Value, 80.0 Shares Authorized, 51.6 and 51.5 Shares Issued and Outstanding	1,431.1	1,428.5
Accumulated Other Comprehensive Loss	(27.2)	(27.3)
Retained Earnings	794.8	754.6
Total Shareholders’ Equity	2,198.7	2,155.8
Total Liabilities and Shareholders' Equity	$ 5,218.8	$ 5,165.0

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

Name:	us-gaap_AccountsPayableCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130549-203045

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(3))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682