Restatement of previously issued financial statements (Details 3) (USD $) In Thousands, unless otherwise specified	9 Months Ended	12 Months Ended
Dec. 31, 2011	Dec. 31, 2012	Mar. 31, 2011
Loss for the period	$ (45,794)	$ (98,774)	$ (42,142)
Other comprehensive income (loss):
Cumulative translation adjustment	(12,370)	3,745	7,414
Comprehensive loss	(58,164)	(95,029)	(34,728)
Comprehensive income (loss) attributable to:
The Company	(58,164)		(34,728)
As previously reported
Loss for the period	(32,836)		(34,357)
Other comprehensive income (loss):
Cumulative translation adjustment	(12,370)		7,414
Comprehensive loss	(45,206)		(26,943)
Comprehensive income (loss) attributable to:
Joint venture partners	12,958		7,785
The Company	(58,164)		(34,728)
Correction
Loss for the period	(12,958)		(7,785)
Other comprehensive income (loss):
Comprehensive loss	(12,958)		(7,785)
Comprehensive income (loss) attributable to:
Joint venture partners	$ (12,958)		$ (7,785)

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the economic entity, including both controlling (parent) and noncontrolling interests. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, including any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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- Definition

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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Reference 8: http://www.xbrl.org/2003/role/presentationRef

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