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Quarterly Financial Information (Unaudited) (Narrative) (Details) $ in Millions	3 Months Ended
	Dec. 31, 2017 USD ($)
Quarterly Financial Data [Abstract]
Tax Cuts and Jobs Act of 2017, Income Expense (Benefit)	$ 7.4

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- Definition

Tax Cuts and Jobs Act of 2017, Income Expense (Benefit)

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

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- References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration