Income Before Taxes (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest [Abstract]
United States	$ 81,482	$ 65,271	$ 52,110
Foreign	4,458	3,429	2,216
Income before taxes	$ 85,940	$ 68,700	$ 54,326

The portion of earnings or loss from continuing operations before income taxes that is attributable to foreign operations, which is defined as Income or Loss generated from operations located outside the entity's country of domicile.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 4

-Section 08

-Paragraph h

-Subparagraph 1(i)

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h)(1)(i))

-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690

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