Quarterly Financial Data (unaudited) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	12 Months Ended
Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012
Revenue	$ 245,921	$ 223,399	$ 156,512	$ 165,615	$ 214,985	$ 197,030	$ 140,988	$ 149,573	$ 791,447	$ 702,576	$ 632,787
Gross profit	78,577	67,672	38,551	40,893	64,321	58,505	32,411	37,245	225,693	192,482	175,067
Net income (loss)	$ 16,681	$ 10,893	$ (10,082)	$ (1,434)	$ 10,253	$ 11,016	$ (8,260)	$ (5,872)	$ 16,058	$ 7,137	$ (62,248)
Basic and diluted earnings (loss) per share	$ 0.22	$ 0.14	$ (0.14)	$ (0.02)	$ 0.14	$ 0.15	$ (0.11)	$ (0.09)	$ 0.20	$ 0.10	$ (1.02)

The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

No definition available.

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Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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