Derivative Instruments and Hedging Activities, Part 2 (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) recognized in OCI on derivatives	$ 0	$ 0	$ 0	$ 126
Amount of gain or (loss) reclassified from accumulated OCI into income	0	63	0	748
Amount of gain (loss) recognized in income on derivatives	0	0	0	4
Designated as Hedging Instrument [Member] | Commodity Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) recognized in OCI on derivatives	0	0	0	126
Amount of gain or (loss) reclassified from accumulated OCI into income	0	63	0	748
Amount of gain (loss) recognized in income on derivatives	0	0	0	4
Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) recognized in income on derivatives	0	(18)	0	1,623
Not Designated as Hedging Instrument [Member] | Commodity Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) recognized in income on derivatives	$ 0	$ (18)	$ 0	$ 1,623