Percentage of eligible inventory value as defined in the credit agreement for borrowing base determination.

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- Definition

Percentage of liquidation, build, constructed or acquired eligible equipment or facility value as defined in the credit agreement for borrowing base determination.

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No definition available.

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- Definition

Maximum amount of capital expenditure that can be incurred next fiscal year under the terms of a credit agreement.

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No definition available.

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Maximum amount of capital expenditure that can be incurred second fiscal year under the terms of a credit agreement.

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No definition available.

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- Definition

Amount of unrestricted cash and cash equivalents of the company can be made as adjustment for indebtedness and senior indebtedness to EBITDA ratio.

+ References

No definition available.

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Ratio of consolidated EBITDA to fixed charges, is a ratio used to measure a company's ability to incur additional debt or its ability to pay off existing debt.

+ References

No definition available.

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- Definition

Ratio of indebtedness to consolidated EBITDA is a measure of leverage ratio.

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No definition available.

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- Definition

Amount of potential additional borrowing capacity under the credit facility.

+ References

No definition available.

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- Definition

Percentage of unrestricted cash and cash equivalents of the company and its subsidiaries can be made as adjustment for indebtedness and senior indebtedness to EBITDA ratio.

+ References

No definition available.

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Ratio of senior indebtedness to consolidated EBITDA is a measure of leverage ratio.

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No definition available.

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- Definition

The number of shares converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition

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

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No definition available.

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- 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

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- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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- Definition

Number of share options (or share units) exercised during the current period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-SubTopic 10
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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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No definition available.

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Subsequent Events (Details) - USD ($) $ in Millions			2 Months Ended	12 Months Ended
Subsequent Events (Details) - USD ($) $ in Millions	Jan. 19, 2018	May 17, 2017	Mar. 06, 2018	Dec. 31, 2017	Dec. 31, 2016
Subsequent event
Options exercised (in shares)				91,484
Credit facility
Subsequent event
Eligible inventory value (as a percent)		65.00%
Credit facility \| Minimum
Subsequent event
Ratio of consolidated EBITDA to fixed charges		1.25%
Credit facility \| Maximum
Subsequent event
Indebtedness to consolidated EBITDA		2.50
Credit facility \| LIBOR \| Minimum
Subsequent event
Applicable margin rate	3.00%	3.00%
Credit facility \| LIBOR \| Maximum
Subsequent event
Applicable margin rate	3.50%	4.00%
Advance Loan Facility
Subsequent event
Maximum borrowing		$ 0.0			$ 10.0
Revolving Facility
Subsequent event
Maximum borrowing		20.0			1.0
Potential addition borrowing available		$ 10.0			$ 1.0
Revolving Facility \| Minimum
Subsequent event
Commitment fee (as a percent)		0.1875%
Revolving Facility \| Maximum
Subsequent event
Commitment fee (as a percent)		0.50%
Subsequent Events \| Credit facility
Subsequent event
Cash adjustment to indebtedness and senior indebtedness ratio	$ 10.0
Percentage of cash adjustment to indebtedness and senior indebtedness ratio	50
Maximum capital expenditures allowed in 2018	$ 225.0
Maximum capital expenditures allowed in 2019	$ 75.0
Subsequent Events \| Credit facility \| Beginning April 1, 2018
Subsequent event
Indebtedness to consolidated EBITDA	3.25
Senior indebtedness to consolidated EBITDA	2.25
Subsequent Events \| Credit facility \| Beginning October 1, 2018
Subsequent event
Indebtedness to consolidated EBITDA	3.00
Senior indebtedness to consolidated EBITDA	2.00
Subsequent Events \| Credit facility \| Minimum
Subsequent event
Indebtedness to consolidated EBITDA	3.50
Senior indebtedness to consolidated EBITDA	2.50
Ratio of consolidated EBITDA to fixed charges	1.25%
Subsequent Events \| Credit facility \| Minimum \| Beginning April 1, 2018
Subsequent event
Indebtedness to consolidated EBITDA	3.50
Senior indebtedness to consolidated EBITDA	2.50
Subsequent Events \| Credit facility \| LIBOR \| Minimum
Subsequent event
Applicable margin rate	3.00%
Subsequent Events \| Credit facility \| LIBOR \| Maximum
Subsequent event
Applicable margin rate	3.50%
Subsequent Events \| Advance Loan Facility
Subsequent event
Maximum borrowing	$ 50.0
Advance loan, as percentage of current net orderly liquidation value	80.00%
Subsequent Events \| Revolving Facility
Subsequent event
Maximum borrowing	$ 20.0
Potential addition borrowing available	$ 10.0
Eligible inventory value (as a percent)	35.00%
Subsequent Events \| Revolving Facility \| Minimum
Subsequent event
Commitment fee (as a percent)	0.25%
Subsequent Events \| Revolving Facility \| Maximum
Subsequent event
Commitment fee (as a percent)	0.50%
Class B Common Stock \| Subsequent Events
Subsequent event
Number of shares converted			5,903,247
Options \| Class A Common Stock \| Subsequent Events
Subsequent event
Options exercised (in shares)			235,396