Number of days that a loan agreement will mature prior to the earliest maturity date.

No definition available.

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- Definition

The amount of increase to the maximum borrowing capacity under the credit facility through an incremental facility.

+ References

No definition available.

+ Details

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- Definition

Sub-limit for letters of credit.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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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.

+ Details

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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

- 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://fasb.org/us-gaap/role/ref/legacyRef
-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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Balance Type:	credit
Period Type:	instant

- Definition

The effective interest rate at the end of the reporting period.

+ References

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
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

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash inflow from amounts received from issuance of long-term debt that is wholly or partially secured by collateral. Excludes proceeds from tax exempt secured debt.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3255-108585

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

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- Details

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- Details

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- Details

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- Details

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Debt - Revolving Credit Facility (Details) - USD ($) $ in Millions		4 Months Ended		9 Months Ended	12 Months Ended
	Nov. 15, 2012	Oct. 08, 2017	Oct. 09, 2016	Oct. 07, 2018	Dec. 31, 2017
Promissory Note
Debt
Gross proceeds		$ 1.8
Revolving Credit Facility
Debt
Maximum borrowing capacity	$ 150.0
Term of debt (in years)	5 years
Increase in borrowing capacity			$ 200.0
Maturity date requirement for payment of Term Loan Facility (in days)			60 days
Rate at period end (as a percent)				5.25%	4.75%
Calculated borrowing base				$ 201.7	$ 206.9
Remaining borrowing capacity				$ 117.9	$ 82.8
Revolving Credit Facility \| Alternate base rate
Debt
Applicable margin (as a percent)				0.25%	0.25%
Rate at period end (as a percent)				5.00%	4.50%
Revolving Credit Facility \| Alternate base rate \| Minimum
Debt
Applicable margin (as a percent)	0.25%		0.25%
Revolving Credit Facility \| Alternate base rate \| Maximum
Debt
Applicable margin (as a percent)	0.75%		0.50%
Revolving Credit Facility \| LIBOR \| Minimum
Debt
Applicable margin (as a percent)	1.25%		1.25%
Revolving Credit Facility \| LIBOR \| Maximum
Debt
Applicable margin (as a percent)	1.75%		1.50%
Revolving Credit Facility \| Letters of credit
Debt
Maximum borrowing capacity	$ 50.0
Sub-limit				$ 65.0
Drawn facility outstanding				$ 47.1	$ 36.2