Note 14 - Derivative Instruments and Fair Value Measurements (Detail) - Derivatives Designated As Cash-Flow Hedges (USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended
Dec. 31, 2011	Dec. 31, 2012
Gains Losses Recognized In OCI On Derivatives [Member]
Commodity derivatives	$ (1,252)	$ (286)
Gains Losses Reclassified From AOCI Into Earnings [Member]
Commodity derivatives	$ (539)	$ (413)

Net of tax and reclassification adjustments amount of the change in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Also includes an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 10A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=20435746&loc=SL7669646-108580

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration