Consolidated Statements of Comprehensive Income (Unaudited) (USD $) In Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Statement of Comprehensive Income [Abstract]
Net income	$ 12,868	$ 10,742	$ 35,222	$ 28,956
Other comprehensive income (loss), net of tax :
Unrealized losses on hedging derivatives	(54)	(66)	(53)	(420)
Unrealized losses on available for sale securities				(4)
Realized gains on available for sale securities				(19)
Comprehensive income	$ 12,814	$ 10,676	$ 35,169	$ 28,513

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

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Reclassification adjustment for unrealized gains or losses realized upon the sale of securities, after tax.

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Change in accumulated gains and losses from derivative instrument designated and qualifying as the effective portion of cash flow hedges, net of tax effect. The after tax effect change includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses.

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