Short-Term and Long-Term Debt - Financial Covenants (Details)	Sep. 30, 2017
Debt Instrument [Line Items]
Actual Ratio of Indebtedness to Total Capitalization	0.42
Maximum [Member]
Debt Instrument [Line Items]
Required Ratio of Indebtedness to Total Capitalization	0.65

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.

No definition available.

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration