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Debt (Narrative) (Details) - USD ($) |  | 1 Months Ended |  |
--- | --- | --- | --- | ---
Dec. 09, 2015 | Jan. 31, 2013 | Dec. 31, 2017 | Dec. 31, 2016
Debt Instrument [Line Items] |  |  |  |
Standby letters of credit |  |  | $ 11,200,000 |
Availability amount |  |  | $ 288,800,000 | $ 287,200,000
Senior Subordinated 6.25% Notes |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Notes issued |  | $ 210,000,000 |  |
Interest rate |  | 6.25% | 6.25% | 6.25%
Revolving Credit Facility | Senior Credit Agreement |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Current borrowing capacity | $ 300,000,000 |  |  |
Maximum borrowing capacity under the revolving credit facility | $ 500,000,000 |  |  |
Revolving Credit Facility | Senior Credit Agreement | Minimum |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Annual commitment fee | 0.20% |  |  |
Revolving Credit Facility | Senior Credit Agreement | Minimum | LIBOR |  |  |  |
Debt Instrument [Line Items] |  |  |  |
LIBOR floor, plus | 1.25% |  |  |
Revolving Credit Facility | Senior Credit Agreement | Maximum |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Annual commitment fee | 0.30% |  |  |
Revolving Credit Facility | Senior Credit Agreement | Maximum | LIBOR |  |  |  |
Debt Instrument [Line Items] |  |  |  |
LIBOR floor, plus | 2.25% |  |  |
Term Loan | Senior Credit Agreement |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Term loan (up to) | $ 200,000,000 |  |  |

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- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399 + Details
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + 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(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition The total amount of the contingent obligation under letters of credit outstanding as of the reporting date. + References No definition available. + Details
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- Definition The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used. + References No definition available. + Details
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- Definition Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility. + 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 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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