Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Operating activities:
Net (loss) income	$ (339)us-gaap_NetIncomeLoss	$ 688us-gaap_NetIncomeLoss
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Depreciation of property, equipment and improvements	752us-gaap_Depreciation	897us-gaap_Depreciation
Amortization of identifiable intangible assets	770us-gaap_AmortizationOfIntangibleAssets	952us-gaap_AmortizationOfIntangibleAssets
Stock-based compensation	1,184us-gaap_ShareBasedCompensation	1,023us-gaap_ShareBasedCompensation
Excess tax benefits from stock-based compensation	0	(20)
Deferred income tax provision (benefit)	412us-gaap_DeferredIncomeTaxExpenseBenefit	(506)us-gaap_DeferredIncomeTaxExpenseBenefit
Bad debt/product return provision	30us-gaap_ProvisionForDoubtfulAccounts	22us-gaap_ProvisionForDoubtfulAccounts
Inventory obsolescence	230us-gaap_InventoryWriteDown	229us-gaap_InventoryWriteDown
Restructuring charges, net	0dgii_RestructuringChargeNet	81dgii_RestructuringChargeNet
Other	(6)us-gaap_OtherNoncashIncomeExpense	102us-gaap_OtherNoncashIncomeExpense
Changes in operating assets and liabilities	2,310	(3,805)
Net cash provided by (used in) operating activities	5,343	(337)
Investing activities:
Purchase of marketable securities	(12,135)	0
Proceeds from maturities of marketable securities	9,321	7,109
Purchase of property, equipment, improvements and certain other intangible assets	(1,469)	(975)
Net cash (used in) provided by investing activities	(4,283)	6,134
Financing activities:
Excess tax benefits from stock-based compensation	0	20
Proceeds from stock option plan transactions	9	2,813
Proceeds from employee stock purchase plan transactions	261us-gaap_ProceedsFromStockPlans	296us-gaap_ProceedsFromStockPlans
Purchases of common stock	(2,257)	0
Net cash (used in) provided by financing activities	(1,987)	3,129
Effect of exchange rate changes on cash and cash equivalents	(1,520)	224
Net (decrease) increase in cash and cash equivalents	(2,447)	9,150
Cash and cash equivalents, beginning of period	47,490	41,320
Cash and cash equivalents, end of period	$ 45,043	$ 50,470

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