Financial instruments by category (Tables)

12 Months Ended

Dec. 31, 2017

Disclosure of detailed information about financial instruments [line items]

Disclosure of detailed information about financial instruments [text block]

	Assets as per statement
Amounts in US$ '000	of financial position
	2017		2016
Loans and receivables
Trade receivables		19,519		18,426
To be recovered from co-venturers (Note 33)		2,455		3,311
Other financial assets (a)		43,488		22,027
Cash and cash equivalents		134,755		73,563
		200,217		117,327

^(a) Non current other financial assets relate to contributions made for environmental obligations according to Colombian and Brazilian government regulations and also include a non current account receivable with the previous owners of one of the Colombian subsidiaries (see Note 28). Current other financial assets corresponds to the security deposit granted in relation to the purchase of Argentinian assets (see Note 35) and short term investments with original maturities up to twelve months and over three months.

	Liabilities as per statement
	of financial position
Amounts in US$ '000	2017		2016
Liabilities at fair value through profit and loss
Derivative financial instrument liabilities		19,289		3,067
		19,289		3,067
Other financial liabilities at amortised cost
Trade payables		52,557		23,650
Payables to related parties (Note 33)		31,184		27,801
To be paid to co-venturers (Note 33)		10,015		1,614
Borrowings		426,204		358,672
		519,960		411,737
Total financial liabilities		539,249		414,804

Disclosure of credit quality of trade receivables [Text Block]

The credit quality of financial assets that are neither past due nor impaired can be assessed by reference to external credit ratings (if available) or to historical information about counterparty default rates:

Amounts in US$ '000	2017		2016
Trade receivables
Counterparties with an external credit rating (Moody’s)
B2		70		7,056
Ba3		8,788		-
Baa3		3,614		3,729
Counterparties without an external credit rating
Group1 (a)		7,047		7,641
Total trade receivables		19,519		18,426

^(a) Group 1 – existing customers (more than 6 months) with no defaults in the past.

Disclosure of maturity analysis for non-derivative financial liabilities [text block]

The table below analyses the Group’s financial liabilities into relevant maturity groupings based on the remaining period at the balance sheet to the contractual maturity date. The amounts disclosed in the table are the contractual undiscounted cash flows.

	Less than 1		Between 1		Between 2		Over 5
Amounts in US$ '000	year		and 2 years		and 5 years		years
At 31 December 2017
Borrowings		27,625		27,625		82,875		480,250
Trade payables		52,557		-		-		-
Payables to related parties		7,331		2,068		27,087		-
		87,513		29,693		109,962		480,250
At 31 December 2016
Borrowings		48,958		43,304		355,064		-
Trade payables		23,650		-		-		-
Payables to related parties		1,561		1,561		22,018		-
		74,169		44,865		377,082		-

Disclosure Of Financial liabilities Measured And Recognised At Fair Value And On Recurring Basis [text block]

The following table presents the Group’s financial assets and financial liabilities measured and recognised at fair value at 31 December 2017 and 2016 on a recurring basis:

			At 31 December
Amounts in US$ '000	Level 2		2017
Liabilities
Derivative financial instrument liabilities
Commodity risk management contracts		19,289		19,289
Total Liabilities		19,289		19,289

			At 31 December
Amounts in US$ '000	Level 2		2016
Liabilities
Derivative financial instrument liabilities
Commodity risk management contracts		3,067		3,067
Total Liabilities		3,067		3,067

Cash At Bank And Other Financial Assets [Member]

Disclosure of detailed information about financial instruments [line items]

Disclosure of credit quality of cash at bank and other financial assets [text block]

All trade receivables are denominated in US Dollars, except in Brazil where are denominated in Brazilian Real.

Cash at bank and other financial assets (a)
Amounts in US$ '000	2017		2016
Counterparties with an external credit rating (Moody’s, S&;P, Fitch, BRC Investor Services)
A1		553		813
A2		298		-
A3		63,853		-
Aaa		15,040		-
Aa3		11,401		42,798
AAA		19,634		14
B2		31		-
Ba1		18		-
Ba2		7		-
Baa1		307		100
Baa2		4,078		4,094
Ba3		2,815		3,497
B3		-		10
BBB		15,064		-
Counterparties without an external credit rating		45,123		44,252
Total		178,222		95,578

^(a) The remaining balance sheet item ‘cash and cash equivalents’ corresponds to cash on hand amounting to US$  21,000 (US$ 12,000 in 2016).