Nature of Operations and Summary of Significant Accounting Policies - Additional Information (Detail)	3 Months Ended	6 Months Ended	12 Months Ended
Mar. 31, 2016 USD ($) Patents Institution	Mar. 31, 2015 USD ($)	Mar. 31, 2016 USD ($) Patents Institution	Mar. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)
Accounting Policies [Abstract]
Number of patents granted \| Patents	25		25
Number of patent applications pending \| Patents	18		18
Number of financial institutions signed agreements to deploy mobile deposit \| Institution	5,007		5,007
Number of top U.S. retail banks that deployed mobile deposit \| Institution	50		50
Foreign currency translation adjustment	$ 1,000	$ 0	$ (129,000)	$ 0
Impairment of goodwill and intangibles			0		$ 0
Other-than-temporary impairment charges recognized	0	0	0	0
Allowance for doubtful accounts receivable	12,300		12,300		12,900
Software development costs capitalized	0	$ 0	0	$ 0
Accumulated other comprehensive loss	$ 125,000		$ 125,000		$ 3,000

Number of financial institutions that signed agreement to deploy mobile deposit.

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Number of patents granted.

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No definition available.

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Number of pending patent applications.

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No definition available.

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- Definition

Number of top retail banks that deployed mobile deposit.

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No definition available.

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- References

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e637-108580

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-Publisher SEC
-Name Regulation S-X (SX)
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-Name Regulation S-X (SX)
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A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.4)
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Unamortized costs incurred for development of computer software, which is to be sold, leased or otherwise marketed, after establishing technological feasibility through to the general release of the software products. Excludes capitalized costs of developing software for internal use.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Publisher SEC
-Name Regulation S-X (SX)
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Total loss recognized during the period from the impairment of goodwill plus the loss recognized in the period resulting from the impairment of the carrying amount of intangible assets, other than goodwill.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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The amount of other than temporary impairment (OTTI) losses on equity securities, OTTI related to credit losses on debt securities, and OTTI losses on debt securities when the entity intends to sell the securities or it is more likely than not that the entity will be required to sell the securities before recovery of its amortized cost basis. Additionally, this item includes OTTI losses recognized during the period on investments accounted for under the cost method of accounting.

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