Quarterly report pursuant to Section 13 or 15(d)

Derivative Financial Instruments - Summary of Open and Closed (Not Settled) Commodity Derivative Contracts (Details)

v3.8.0.1
Derivative Financial Instruments - Summary of Open and Closed (Not Settled) Commodity Derivative Contracts (Details)
$ in Thousands
Sep. 30, 2017
USD ($)
Derivatives Fair Value [Line Items]  
Derivative assets $ 1,155 [1]
Open Contracts  
Derivatives Fair Value [Line Items]  
Derivative assets 841
Closed Contracts - Not Settled  
Derivatives Fair Value [Line Items]  
Derivative assets $ 314
[1] Includes open and closed (and not settled) derivative commodity contracts recorded at fair value.