Condensed Consolidated Statements of Operations and Other Comprehensive Income (Unaudited) (USD $) In Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Comprehensive Income [Abstract]
Net income	$ 1,825	$ 13,302	$ 822	$ 39,883
Amortization of actuarial loss on defined benefit plan (note 16(a))	53		107
Unrealized hedging gain (loss) (note 17(d))	49	(387)	351	(179)
Realization of hedging (gains) losses upon settlement (note 17(d))	(466)	7	(724)	(542)
Unrealized change in market value of available-for-sale investment (note 17(e))	(488)		(488)
Tax effect of movement in comprehensive income (note 13(b))	164	0	136	0
Comprehensive income, net of income taxes	$ 1,137	$ 12,922	$ 204	$ 39,162

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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+ Details

- Definition

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ References+ Details

- Definition

The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

+ References+ Details

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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+ Details

- Definition

Tax effect of the change in accumulated other comprehensive income (loss), that is, the tax effect on items included in other comprehensive income (loss) during the period.

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The net gain (loss) previously recognized in other comprehensive income that is a reclassification adjustment of other comprehensive income as a result of being recognized as a component of net periodic benefit cost for the period.

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- Definition

Gross appreciation or the gross loss in value of the total of unsold available-for-sale securities during the period being reported (except when designated as a fair value hedge).

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