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Debt and Financing Arrangements (Details) - USD ($) | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017 | Sep. 27, 2013
Debt Instrument [Line Items] |  |  |  |  |
Additional borrowings available |  |  |  |  | $ 75,000,000
Long-term debt | $ 23,100,000 |  | $ 23,100,000 |  |
Other, Net |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Payments of financing costs | 300,000 | $ 700,000 | $ 800,000 | $ 1,600,000 |
LIBOR Rate |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Basis spread on variable rate |  |  | 3.10% |  |
Term Loan |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Partial repayment of debt | 25,000,000.0 |  |  |  |
Term Loan and Revolving Facility |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Partial repayment of debt | 26,900,000 |  | $ 54,900,000 |  |
Revolving Facility |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Principal amount |  |  |  |  | 150,000,000
Long-term debt | 0 |  | 0 |  |
Term Loan |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Principal amount |  |  |  |  | 150,000,000
Long-term debt | 23,100,000 |  | 23,100,000 |  |
Annual principal repayments | $ 7,500,000 |  | $ 7,500,000 |  |
Credit Agreement |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Additional borrowings available |  |  |  |  | 75,000,000
Swing Loans |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Additional borrowings available |  |  |  |  | 20,000,000
Letter of Credit |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Additional borrowings available |  |  |  |  | $ 20,000,000

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- Definition Amount of the total principal payments made during the annual reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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