Condensed Consolidated Statements of Comprehensive Income (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2015	Mar. 31, 2014
Statement of Comprehensive Income [Abstract]
Net earnings	$ 10,070us-gaap_NetIncomeLoss	$ 10,300us-gaap_NetIncomeLoss	$ 17,971us-gaap_NetIncomeLoss	$ 17,726us-gaap_NetIncomeLoss
Foreign currency translation adjustment	(2,138)	337	(3,503)	1,060
COMPREHENSIVE INCOME	$ 7,932us-gaap_ComprehensiveIncomeNetOfTax	$ 10,637us-gaap_ComprehensiveIncomeNetOfTax	$ 14,468us-gaap_ComprehensiveIncomeNetOfTax	$ 18,786us-gaap_ComprehensiveIncomeNetOfTax

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

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