Commitments And Contingencies: Environmental Contingencies (Details) $ in Millions	Dec. 31, 2015 USD ($)
Electric Utilities [Member]
Loss Contingencies [Line Items]
Accrual for Environmental Loss Contingencies	$ 3.9
Manufactured Gas Plant [Member] \| Gas Utilities [Member]
Loss Contingencies [Line Items]
Insurance Settlements Receivable, Noncurrent	1.4
Loss Contingency, Range of Possible Loss, Minimum	2.9
Loss Contingency, Range of Possible Loss, Maximum	6.1
Accrual for Environmental Loss Contingencies, Gross	$ 2.6

Total costs accrued as of the balance sheet date for environmental loss contingencies.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 410
-SubTopic 30
-Section 50
-Paragraph 7
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Undiscounted amount of the accrual for environmental loss contingencies.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Carrying amount due after one year of the balance sheet date (or one operating cycle, if longer) of amount due in settlement of a claim for reimbursement from an insurance company when the Company has suffered a loss covered under an insurance policy.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The estimated minimum amount of possible loss from the contingency.

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