Condensed Consolidated Statement Of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Statement of Other Comprehensive Income [Abstract]
Net income	$ 72,831	$ 65,468
Other comprehensive income (loss)
Interest rate swaps	372	(208)
Other comprehensive income (loss)	372	(208)
Total comprehensive income	$ 73,203	$ 65,260

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.

+ 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 7: http://www.xbrl.org/2003/role/presentationRef

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

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Reference 16: http://www.xbrl.org/2003/role/presentationRef

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+ Details

- Definition

Net of tax and reclassification adjustments amount of the change in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges, which is attributable to the parent entity. Also includes an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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+ Details