Financial Instruments (Tables)

6 Months Ended

Jun. 30, 2016

Derivative [Line Items]

Fair Value of Financial Assets and Liabilities

The tables below summarize the balances of commodity derivative assets and liabilities at June 30, 2016 and December 31, 2015 (in thousands):

	June 30, 2016							December 31, 2015
Derivatives subject to netting arrangements:	Level 1		Netting*			Total		Level 1		Netting*			Total
Commodity derivatives:
Assets	$	1,160	$	(1,160	)	$	—	$	131	$	(131	)	$	—
Liabilities	$	1,428	$	(1,160	)	$	268	$	470	$	(131	)	$	339

*Relates primarily to exchange traded futures. Gain and loss positions on multiple contracts are settled net on a daily basis with the exchange.

Schedule of Notional Quantities for Commodity Derivative Instruments

The following table sets forth the notional quantities for commodity derivative instruments entered into (in thousands of barrels):

	Three Months Ended June 30,		Six Months Ended June 30,
	2016	2015	2016	2015
Sales	5,890	7,721	16,310	13,452
Purchases	5,743	7,508	16,253	13,413

Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block]

We have recorded the fair value of our commodity derivative instruments on our condensed consolidated balance sheets in other current assets and other current liabilities in the following amounts (in thousands):

	June 30, 2016				December 31, 2015
	Assets		Liabilities		Assets		Liabilities
Commodity contracts	$	—	$	268	$	—	$	339

Schedule of Realized and Unrealized Gains (Losses) from Commodity Derivatives

Realized and unrealized gains (losses) from our commodity derivatives were recorded to product revenue in the following amounts (in thousands):

	Three Months Ended June 30,						Six Months Ended June 30,
	2016			2015			2016			2015
Commodity contracts	$	(7,127	)	$	(2,202	)	$	(3,773	)	$	(2,268	)