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Operations and Significant Accounting Policies - Revision of Prior Balance Sheet (Details) $ in Millions	12 Months Ended
	Dec. 31, 2016 USD ($)
Deferred Income Taxes [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Immaterial Revision	$ 29.5

X

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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X

- Definition

Amount of each individual error being corrected in the correcting adjustment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 1.N)
-URI http://asc.fasb.org/extlink&oid=26874127&loc=d3e30840-122693

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- Details

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