Investment in associated companies (Tables)

12 Months Ended

Dec. 31, 2012

Investment in associated companies [Abstract]

Percentages of ownership and book value of investments recorded using equity method

The Company has the following investments that are recorded using the equity method:

	December 31, 2012			December 31, 2011			December 31, 2010
SapuraCrest Bhd ("SapuraCrest")*		-	*		23.6	%		23.6	%
Varia Perdana Sdn Bhd ("Varia Perdana")		49.0	%		49.0	%		49.0	%
Tioman Drilling Company Sdn Bhd ("Tioman")		49.0	%		49.0	%		49.0	%
C6 Technologies AS ("C6")***		-			-			50.0	%
Archer ("Archer")***		39.9	%		39.9	%		-
Asia Offshore Drilling ("AOD")**		66.2	%		33.8	%		-
Sevan Drilling ("Sevan Drilling")		28.5	%		28.5	%		-
Seabras Sapura Participacoes SA ("Seabras Sapura Participacoes")		50	%		-			-
Seabras Sapura Holdco Ltd ("Seabras Sapura Holdco")		50	%		-			-
Itaunas Drilling B.V. ("Itaunas Drilling")		30	%		-			-
Camburi Drilling B.V. ("Camburi Drilling")		30	%		-			-
Sahy Drilling B.V. ("Sahy Drilling")		30	%		-			-

Summarized balance sheet information of equity method investees

Summarized balance sheet information of the Company's equity method investees is as follows:

	As of December 31, 2012
(In US$ millions)	Current assets		Non-current assets		Current liabilities		Non-current liabilities
Varia Perdana		98		154		37		-
Tioman		82		1		61		-
Archer		639		1,945		685		972
AOD		32		141		6		-
Sevan Drilling		133		1,586		266		791
Seabras Sapura Participacoes		-		42		-		-
Seabras Sapura Holdco		-		117		-		117
Itaunas Drilling		5		114		109		-
Camburi Drilling		4		121		113		-
Sahy Drilling		2		109		66		36
TOTAL		995		4,330		1,343		1,916

	As of December 31, 2011
(In US$ millions)	Current assets		Non-current assets		Current liabilities		Non-current liabilities
SapuraCrest		716		514		505		198
Varia Perdana		136		157		64		33
Tioman		80		-		70		-
Archer		638		2,176		466		1,061
AOD		49		122		3		-
Sevan Drilling		224		1,375		117		810
TOTAL		1,843		4,344		1,225		2,102

Summarized statement of operations information for the Company's equity method investees is as follows:

Summarized statement of operations information of equity method investees

Summarized statement of operations information for the Company's equity method investees is as follows:

	Year ended December 31, 2012
(In US$ millions)	Operating revenues		Net operating income			Net income
Varia Perdana		106		85			83
Tioman		157		12			6
Archer		2,191		(322	)		(375	)
AOD		-		(2	)		(2	)
Sevan Drilling		173		11			(12	)
Seabras Sapura Participacoes		-		-			(1	)
Seabras Sapura Holdco		-		-			-
Itaunas Drilling		-		-			-
Camburi Drilling		-		-			-
Sahy Drilling		-		(1	)		(1	)
TOTAL		2,627		(217	)		(302	)

	Year ended December 31, 2011
(In US$ millions)	Operating revenues		Net operating income			Net income
SapuraCrest		866		166			147
Varia Perdana		119		96			96
Tioman		190		(2	)		(4	)
Archer		1,855		(16	)		(77	)
AOD		-		(4	)		(4	)
Sevan Drilling		116		8			(50	)
TOTAL		3,146		248			108

	Year ended December 31, 2010
(In US$ millions)	Operating revenues		Net operating income			Net income
SapuraCrest		1,043		118			122
Varia Perdana		164		99			99
Tioman		247		9			5
C6		-		(1	)		(1	)
TOTAL		1,454		225			225

Recorded equity in the statutory accounts of equity method investees

At the year-end the book values of the Company's investment in associated companies are as follows:

(In US$ millions)	December 31, 2012		December 31, 2011
SapuraCrest		-		106
Tioman		7		1
Varia Perdana		108		102
Archer		121		393
AOD		117		53
Sevan Drilling		66		66
Seabras Sapura Participacoes		21		-
Seabras Sapura Holdco		59		-
Itaunas Drilling		3		-
Camburi Drilling		4		-
Sahy Drilling		3		-
Total		509		721

The quoted market prices for Archer, AOD and Sevan Drilling as at December 31, 2012, were $121 million, 137 million and 68 million, respectively. Quoted market prices for all our other equity investments are not available because these companies are not publicly traded

At year-end the share of recorded equity in the statutory accounts of the Company's associated companies are as follows:

(In US$ millions)	December 31, 2012		December 31, 2011		December 31, 2010
SapuraCrest		-		124		112
Tioman		10		5		7
Varia Perdana		105		96		100
C6		-		-		6
Archer		370		514		-
AOD		110		57		-
Sevan Drilling		189		188		-
Seabras Sapura Participacoes		22		-		-
Seabras Sapura Holdco		-		-		-
Itaunas Drilling		3		-		-
Camburi Drilling		4		-		-
Sahy Drilling		3		-		-
Total		816		984		225