Financial Instruments and Off-Balance Sheet Risk - Summary of Financial Assets and Financial Liabilities of Partnership Measured at Fair Value on Recurring Basis (Detail) - USD ($)
$ in Thousands |
Dec. 31, 2016 |
Dec. 31, 2015 |
| Financial assets: |
|
|
| Financial assets |
$ 66,858
|
$ 157,714
|
| Financial liabilities: |
|
|
| Financial liabilities |
95,339
|
37,178
|
| Commodity fixed forwards |
|
|
| Financial assets: |
|
|
| Financial assets |
65,618
|
157,389
|
| Financial liabilities: |
|
|
| Financial liabilities |
94,875
|
31,801
|
| Commodity swaps and options |
|
|
| Financial assets: |
|
|
| Financial assets |
0
|
51
|
| Financial liabilities: |
|
|
| Financial liabilities |
103
|
4,250
|
| Commodity derivatives |
|
|
| Financial assets: |
|
|
| Financial assets |
65,618
|
157,440
|
| Financial liabilities: |
|
|
| Financial liabilities |
94,978
|
36,051
|
| Interest rate swaps |
|
|
| Financial assets: |
|
|
| Financial assets |
1,240
|
274
|
| Financial liabilities: |
|
|
| Financial liabilities |
336
|
1,115
|
| Other |
|
|
| Financial liabilities: |
|
|
| Financial liabilities |
25
|
12
|
| Quoted Prices in Active Markets Level 1 |
|
|
| Financial assets: |
|
|
| Financial assets |
0
|
0
|
| Financial liabilities: |
|
|
| Financial liabilities |
0
|
0
|
| Quoted Prices in Active Markets Level 1 | Commodity derivatives |
|
|
| Financial liabilities: |
|
|
| Financial liabilities |
0
|
0
|
| Quoted Prices in Active Markets Level 1 | Other |
|
|
| Financial liabilities: |
|
|
| Financial liabilities |
0
|
0
|
| Significant Other Observable Inputs Level 2 |
|
|
| Financial assets: |
|
|
| Financial assets |
66,858
|
157,714
|
| Financial liabilities: |
|
|
| Financial liabilities |
95,339
|
37,178
|
| Significant Other Observable Inputs Level 2 | Commodity fixed forwards |
|
|
| Financial assets: |
|
|
| Financial assets |
65,618
|
157,389
|
| Financial liabilities: |
|
|
| Financial liabilities |
94,875
|
31,801
|
| Significant Other Observable Inputs Level 2 | Commodity swaps and options |
|
|
| Financial assets: |
|
|
| Financial assets |
0
|
51
|
| Financial liabilities: |
|
|
| Financial liabilities |
103
|
4,250
|
| Significant Other Observable Inputs Level 2 | Commodity derivatives |
|
|
| Financial assets: |
|
|
| Financial assets |
65,618
|
157,440
|
| Financial liabilities: |
|
|
| Financial liabilities |
94,978
|
36,051
|
| Significant Other Observable Inputs Level 2 | Interest rate swaps |
|
|
| Financial assets: |
|
|
| Financial assets |
1,240
|
274
|
| Financial liabilities: |
|
|
| Financial liabilities |
336
|
1,115
|
| Significant Other Observable Inputs Level 2 | Other |
|
|
| Financial liabilities: |
|
|
| Financial liabilities |
25
|
12
|
| Significant Unobservable Inputs Level 3 |
|
|
| Financial assets: |
|
|
| Financial assets |
0
|
0
|
| Financial liabilities: |
|
|
| Financial liabilities |
0
|
0
|
| Significant Unobservable Inputs Level 3 | Other |
|
|
| Financial liabilities: |
|
|
| Financial liabilities |
$ 0
|
$ 0
|