XML 31 R79.htm IDEA: XBRL DOCUMENT v2.4.0.6

Subsequent Events - Additional Information (Detail) (Subsequent Event [Member])	Jan. 31, 2013 Barrels
2013 swaps and three-way costless collar options [Member]
Subsequent Event [Line Items]
Total notional amount of oil barrels	334,000
2014 swaps and three-way costless collar options [Member]
Subsequent Event [Line Items]
Total notional amount of oil barrels	699,000
2015 swaps and three-way costless collar options [Member]
Subsequent Event [Line Items]
Total notional amount of oil barrels	62,000

X

- Definition

Aggregate notional amount of derivative expressed in nonmonetary units. For example, the number of barrels specified in a fuel oil forward purchase contract.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

+ Details

Name:	invest_DerivativeNonmonetaryNotionalAmount
Namespace Prefix:	invest_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

X

- Details

Name:	us-gaap_SubsequentEventLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration