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Long-Term Debt - Schedule of Long-Term Debt Interest Rate (Detail) | 9 Months Ended
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Sep. 30, 2015
Less than .25 to 1 [Member] | Maximum [Member] |
Debt Instrument [Line Items] |
Ratio of Total Outstanding Borrowings to Borrowing Base | 0.25
Less than .25 to 1 [Member] | LIBOR [Member] |
Debt Instrument [Line Items] |
Debt instrument interest rate terms, in percentage | 1.50%
Less than .25 to 1 [Member] | ABR [Member] |
Debt Instrument [Line Items] |
Debt instrument interest rate terms, in percentage | 0.00%
Greater than or equal to .25 to 1 but less than .50 to 1 [Member] | Maximum [Member] |
Debt Instrument [Line Items] |
Ratio of Total Outstanding Borrowings to Borrowing Base | 0.5
Greater than or equal to .25 to 1 but less than .50 to 1 [Member] | Minimum [Member] |
Debt Instrument [Line Items] |
Ratio of Total Outstanding Borrowings to Borrowing Base | 0.25
Greater than or equal to .25 to 1 but less than .50 to 1 [Member] | LIBOR [Member] |
Debt Instrument [Line Items] |
Debt instrument interest rate terms, in percentage | 1.75%
Greater than or equal to .25 to 1 but less than .50 to 1 [Member] | ABR [Member] |
Debt Instrument [Line Items] |
Debt instrument interest rate terms, in percentage | 0.25%
Greater than or equal to .50 to 1 but less than .75 to 1 [Member] | Maximum [Member] |
Debt Instrument [Line Items] |
Ratio of Total Outstanding Borrowings to Borrowing Base | 0.75
Greater than or equal to .50 to 1 but less than .75 to 1 [Member] | Minimum [Member] |
Debt Instrument [Line Items] |
Ratio of Total Outstanding Borrowings to Borrowing Base | 0.5
Greater than or equal to .50 to 1 but less than .75 to 1 [Member] | LIBOR [Member] |
Debt Instrument [Line Items] |
Debt instrument interest rate terms, in percentage | 2.00%
Greater than or equal to .50 to 1 but less than .75 to 1 [Member] | ABR [Member] |
Debt Instrument [Line Items] |
Debt instrument interest rate terms, in percentage | 0.50%
Greater than or equal to .75 to 1 but less than .90 to 1 [Member] | Maximum [Member] |
Debt Instrument [Line Items] |
Ratio of Total Outstanding Borrowings to Borrowing Base | 0.9
Greater than or equal to .75 to 1 but less than .90 to 1 [Member] | Minimum [Member] |
Debt Instrument [Line Items] |
Ratio of Total Outstanding Borrowings to Borrowing Base | 0.75
Greater than or equal to .75 to 1 but less than .90 to 1 [Member] | LIBOR [Member] |
Debt Instrument [Line Items] |
Debt instrument interest rate terms, in percentage | 2.25%
Greater than or equal to .75 to 1 but less than .90 to 1 [Member] | ABR [Member] |
Debt Instrument [Line Items] |
Debt instrument interest rate terms, in percentage | 0.75%
Greater than .90 to 1 but less than or equal 1 [Member] | Minimum [Member] |
Debt Instrument [Line Items] |
Ratio of Total Outstanding Borrowings to Borrowing Base | 0.9
Greater than .90 to 1 but less than or equal 1 [Member] | LIBOR [Member] |
Debt Instrument [Line Items] |
Debt instrument interest rate terms, in percentage | 2.50%
Greater than .90 to 1 but less than or equal 1 [Member] | ABR [Member] |
Debt Instrument [Line Items] |
Debt instrument interest rate terms, in percentage | 1.00%

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- Definition The effective interest rate during the reporting period. + 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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