Derivative Financial Instruments - Fair Value (Details) - USD ($) $ in Thousands |
Dec. 31, 2015 |
Sep. 30, 2015 |
Dec. 31, 2014 |
|---|---|---|---|
| Derivative [Line Items] | |||
| Asset (liability) at fair value | $ 3,696 | $ 1,591 | |
| Netting effect | (9) | (69) | |
| Net fair value | 3,705 | $ 3,705 | 1,660 |
| Other Current Assets [Member] | |||
| Derivative [Line Items] | |||
| Asset at fair value | 3,705 | 1,660 | |
| Netting effect, asset | 0 | 0 | |
| Asset | 3,705 | 1,660 | |
| Other Noncurrent Assets | |||
| Derivative [Line Items] | |||
| Asset at fair value | 0 | 0 | |
| Netting effect, asset | 0 | 0 | |
| Asset | 0 | 0 | |
| Other Current Liabilities [Member] | |||
| Derivative [Line Items] | |||
| Liability at fair value | (9) | (69) | |
| Netting effect, liability | 9 | 69 | |
| Liability | 0 | 0 | |
| Other Noncurrent Liabilities [Member] | |||
| Derivative [Line Items] | |||
| Liability at fair value | 0 | 0 | |
| Netting effect, liability | 0 | 0 | |
| Liability | $ 0 | $ 0 |