Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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Data Type:	num:percentItemType
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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

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-Publisher FASB
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-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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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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Balance Type:	credit
Period Type:	instant

- 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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Period Type:	duration

- 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

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Balance Type:	credit
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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Balance Type:	credit
Period Type:	instant

- Definition

The fair value of notes issued in noncash investing and financing activities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
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Balance Type:	credit
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- Details

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Debt (Narrative) (Details) - USD ($)		1 Months Ended
Debt (Narrative) (Details) - USD ($)	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