Derivative underlying hedge percent.

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13433-108611

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-Paragraph 1
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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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- Definition

Nominal volume used to calculate payments on a derivative instrument.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Fixed price related to the price risk swap derivative.

+ 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

Fair value of all derivative liabilities designated as fair value hedging instruments.

+ References

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-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
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- Definition

Amount after tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

+ References

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- Details

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- Details

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Fair Value Measurements (Narrative) (Details) gal in Millions	1 Months Ended	3 Months Ended		6 Months Ended
	May 31, 2017 USD ($)	Jun. 30, 2019 USD ($) $ / gal	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($) $ / gal gal	Jun. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)
Derivatives Fair Value [Line Items]
Derivative underlying hedge percent				80.00%
Derivative, Nonmonetary Notional Amount, Volume \| gal				8.5
Fair value hedge liabilities		$ 678,000		$ 678,000		$ 4,710,000
Reclassification of derivative gains (losses) to earnings—net of tax		(295,000)	$ 1,037,000	(1,186,000)	$ 1,769,000
8.000% Senior Notes Due in 2022 [Member]
Derivatives Fair Value [Line Items]
Debt instrument, face amount	$ 325,000,000
Stated interest rate	8.00%
Maturity date	May 15, 2022
8.000% Senior Notes Due in 2022 [Member] \| Fair Value, Inputs, Level 1 [Member]
Derivatives Fair Value [Line Items]
Fair value of debt		$ 344,110,000		$ 344,110,000
Minimum [Member]
Derivatives Fair Value [Line Items]
Fixed price range \| $ / gal		1.86		1.86
Maximum [Member]
Derivatives Fair Value [Line Items]
Fixed price range \| $ / gal		2.34		2.34