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Income Taxes - Open Tax Years (Details)	12 Months Ended
	Dec. 31, 2017
Domestic Tax Authority | Earliest Tax Year
Income Taxes [Line Items]
Open tax year	2014
Domestic Tax Authority | Latest Tax Year
Income Taxes [Line Items]
Open tax year	2017
State and Local Jurisdiction | Earliest Tax Year
Income Taxes [Line Items]
Open tax year	2013
State and Local Jurisdiction | Latest Tax Year
Income Taxes [Line Items]
Open tax year	2017

X

- Definition

[Line Items] for Income Taxes [Table]

+ References

No definition available.

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- Definition

Tax year that remains open to examination under enacted tax laws, in CCYY format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319

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