Voluntary Reimbursements to Ohio Customers (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Dec. 04, 2012
Voluntary Reimbursements [Abstract]
Number Of Customers Reimbursed		14,000
Ohio Reimbursements Expense	$ 13.4
Payments made to customer	$ 0

Amount of refund payments made to customers during the period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 605

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 13.A.4(a))

-URI http://asc.fasb.org/extlink&oid=6600647&loc=d3e214044-122780

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 13

-Section A

-Paragraph a

-Subsection 4

Name:	us-gaap_CustomerRefundableFeesRefundPayments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration