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Summary of Significant Accounting Policies - Additional Information (Details) - USD ($) | 12 Months Ended
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Sep. 30, 2016 | Sep. 30, 2015 | Sep. 30, 2014
Significant Accounting Policies [Line Items] |  |  |
Minimum credit limit | 30 days |  |
Extended credit terms for trade receivables | 60 days |  |
Account receivable | $ 15,392,000 | $ 12,693,000 |
Impairment of rental assets | $ 1,814,000 |  |
Requisite service period | 1 year 6 months |  |
Shipping and handling costs | $ 400,000 | $ 600,000 | $ 900,000
Maximum |  |  |
Significant Accounting Policies [Line Items] |  |  |
Requisite service period | 4 years |  |
Customer one |  |  |
Significant Accounting Policies [Line Items] |  |  |
Account receivable | $ 9,100,000 |  |
Customer Concentration Risk | Customer one | Sales Revenue, Net |  |  |
Significant Accounting Policies [Line Items] |  |  |
Percentage of company revenue | 18.50% |  | 26.40%
Customer Concentration Risk | No customers | Sales Revenue, Net |  |  |
Significant Accounting Policies [Line Items] |  |  |
Percentage of company revenue |  | 10.00% |
Current assets |  |  |
Significant Accounting Policies [Line Items] |  |  |
Effect of retrospective adjustment due to accounting standard update |  | $ (6,400,000) |
Current liabilities |  |  |
Significant Accounting Policies [Line Items] |  |  |
Effect of retrospective adjustment due to accounting standard update |  | (10,000) |
Non-Current deferred tax assets |  |  |
Significant Accounting Policies [Line Items] |  |  |
Effect of retrospective adjustment due to accounting standard update |  | 3,000,000 |
Non-Current deferred tax liabilities |  |  |
Significant Accounting Policies [Line Items] |  |  |
Effect of retrospective adjustment due to accounting standard update |  | $ (3,400,000) |

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- Definition Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection. + 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(3)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: 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)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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