Comprehensive Income (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Comprehensive Income
Net income	$ 26,774	$ 22,106	$ 70,961	$ 69,230
Foreign currency translation adjustments	(4,880)	543	3,313	6,120
Net unrealized gain (loss) from cash flow hedges	(1,288)	(232)	840	(9,305)
Comprehensive income	$ 20,606	$ 22,417	$ 75,114	$ 66,045

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

Net of tax effect change in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges, that is attributable to the parent entity. The change includes an entity's share of an equity investee's increase (decrease) in deferred hedging gains or losses.

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+ Details

- Definition

Adjustment that results from the process of translating subsidiary financial statements and foreign equity investments into functional currency of the reporting entity, net of tax, attributable to the parent entity.

+ References

+ Details

- 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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