Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	6 Months Ended
Mar. 31, 2015	Mar. 31, 2014
CASH FLOWS FROM OPERATING ACTIVITIES
Net earnings	$ 17,971us-gaap_NetIncomeLoss	$ 17,726us-gaap_NetIncomeLoss
Non-cash items included in net earnings:
Depreciation of property, plant and equipment	1,832us-gaap_Depreciation	1,756us-gaap_Depreciation
Amortization of intangible assets	900us-gaap_AmortizationOfIntangibleAssets	1,042us-gaap_AmortizationOfIntangibleAssets
Amortization of deferred illumigene instrument costs	754	864
Stock-based compensation	1,954us-gaap_ShareBasedCompensation	2,157us-gaap_ShareBasedCompensation
Deferred income taxes	(257)us-gaap_DeferredIncomeTaxExpenseBenefit	(31)us-gaap_DeferredIncomeTaxExpenseBenefit
Change in current assets	(6,910)	(6,656)
Change in current liabilities	3,368	(3,143)
Other, net	419	(159)
Net cash provided by operating activities	20,031	13,556
CASH FLOWS FROM INVESTING ACTIVITIES
Purchases of property, plant and equipment	(2,561)	(2,573)
Purchases of intangible assets		(1,677)
Net cash used for investing activities	(2,561)	(4,250)
CASH FLOWS FROM FINANCING ACTIVITIES
Dividends paid	(16,671)us-gaap_PaymentsOfDividendsCommonStock	(16,169)us-gaap_PaymentsOfDividendsCommonStock
Proceeds and tax benefits from exercises of stock options	654	540
Net cash used for financing activities	(16,017)	(15,629)
Effect of Exchange Rate Changes on Cash and Equivalents	(1,781)	254
Net Decrease in Cash and Equivalents	(328)	(6,069)
Cash and Equivalents at Beginning of Period	43,047	44,282
Cash and Equivalents at End of Period	$ 42,719	$ 38,213

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.