Dispositions Dispositions (Details 2) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Sale Leaseback Transaction And Divestiture Of Businesses [Abstract]
Proceed from sale of business	$ 4,300
Net gain on sale of business	$ 3,807	$ 0	$ 3,807	$ 0
Impact from sale on diluted EPS (in dollars per share)	$ 0.02

Impact of Sale of Business Unit on Earnings Per Share, Diluted

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- Definition

Sale Leaseback Transaction And Divestiture Of Businesses [Abstract]

+ References

No definition available.

+ Details

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- Definition

Gain (loss) from sale or disposal of an organization or integrated set of activities (for example, but not limited to, a partnership or corporation) engaged in providing a product or service in a commercial, industrial, or professional environment.

+ References

No definition available.

+ Details

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- Definition

The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3179-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

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