Long-Term Debt (Tables)

12 Months Ended

Dec. 31, 2011

Debt Disclosure [Abstract]

Schedule of Borrowing Base Utilization [Table Text Block]

Borrowing Base Utilization Percentage	<25%		≥25% <50%		≥50% <75%		≥75% <90%		≥90%
Eurodollar Loans	1.500	%	1.750	%	2.000	%	2.250	%	2.500	%
ABR Loans or Swingline Loans	0.500	%	0.750	%	1.000	%	1.250	%	1.500	%
Commitment Fee Rate	0.375	%	0.375	%	0.500	%	0.500	%	0.500	%

Schedule of Debt Instrument, Redemption Price, 6.50% Senior Notes [Table Text Block]

2016	103.250	%
2017	102.167	%
2018	101.083	%
2019 and thereafter	100.000	%

Schedule of Debt Instrument, Redemption Price, 6.625% Senior Notes [Table Text Block]

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