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Intangible Assets - (Notes) | 6 Months Ended
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Mar. 31, 2018
Intangible Assets [Abstract] |
Intangible Assets Disclosure [Text Block] | Intangible Assets The gross and net carrying values of intangible assets as of the balance sheet dates, by major intangible asset class are as follows (in millions):
| March 31, 2018 |  | September 30, 2017
| Gross Amount |  | Accumulated Amortization |  | Net Amount |  | Gross Amount |  | Accumulated Amortization |  | Net Amount
Intangible assets subject to amortization: |  |  |  |  |  |  |  |  |  |  |
Software programs/platforms | 2.7 |  |  | (2.5 | ) |  | 0.2 |  |  | 2.7 |  |  | (2.5 | ) |  | 0.2 |
Customer base | 20.0 |  |  | (9.0 | ) |  | 11.0 |  |  | 20.0 |  |  | (7.9 | ) |  | 12.1 |
Total intangible assets | $ | 22.7 |  |  | $ | (11.5 | ) |  | $ | 11.2 |  |  | $ | 22.7 |  |  | $ | (10.4 | ) |  | $ | 12.3 |
Amortization expense related to intangible assets was $1.1 million and $1.4 million for the six months ended March 31, 2018 and 2017, respectively. As of March 31, 2018, the estimated future amortization expense was as follows:
(in millions) |
Fiscal 2018 (remaining six months) | $ | 1.1 |
Fiscal 2019 | 2.2 |
Fiscal 2020 | 2.0 |
Fiscal 2021 | 1.9 |
Fiscal 2022 and thereafter | 4.0 |
| $ | 11.2 |

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- Definition Intangible Assets [Abstract] + References No definition available. + Details
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- Definition The entire disclosure for all or part of the information related to intangible assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -URI http://asc.fasb.org/topic&trid=2144416 + Details
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