Note 3 - Receivables, Accounts Payable and Accrued Liabilities (Details) - Value-Added Tax Receivable (USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended
	Jun. 30, 2013	Dec. 31, 2012
Value-Added Tax Receivable [Abstract]
Value-added tax receivable as of the beginning of the period	$ 21,784	$ 24,720
IGV accrued related to expenditures during period	7,445	67,846
IGV reduced related to sale of oil during period	(12,934)	(46,586)
IGV related to the sale of a 49% participating interest in Block Z-1	0	(24,196)
Value-added tax receivable as of the end of the period	16,295	21,784
Current portion of value-added tax receivable as of the end of the period	14,817	20,569
Long-term portion of value-added tax receivable as of the end of the period	$ 1,478	$ 1,215