Condensed Consolidated Statements of Comprehensive Income (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Condensed Consolidated Statements of Comprehensive Income [Abstract]
Net income	$ 9,806	$ 17,917	$ 26,590	$ 30,417
Other comprehensive income (loss):
Foreign currency translation adjustment	12	(95)	(16)	(120)
Comprehensive income	$ 9,818	$ 17,822	$ 26,574	$ 30,297

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.

+ References+ Details

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

+ References

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

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+ Details

- Definition

Amount after tax, before reclassification adjustments, resulting from the process of expressing in the reporting currency of the reporting entity those amounts that are denominated or measured in a different currency, and from transactions whose terms are denominated in a currency other than the entity's functional currency.

+ References

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+ Details