Statements Of Cash Flows Parenthetical - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2016	Sep. 30, 2015
Payments To Fund Decommissioning Fund	$ 3.4	$ 3.4

The cash outflow for the purchase of investments that will be held in a decommissioning trust fund.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3213-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

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Balance Type:	credit
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