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Intangible Assets (Notes) | 12 Months Ended
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Sep. 30, 2017
Intangible Assets [Abstract] |
Intangible Assets Disclosure [Text Block] | Intangible Assets During the year ended September 30, 2017, the Company recorded additional customer base intangible assets of $6.0 million as part of the ICAP acquisition. See Note 19 - Acquisitions for additional discussion. 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):
| September 30, 2017 |  | September 30, 2016
| Gross Amount |  | Accumulated Amortization |  | Net Amount |  | Gross Amount |  | Accumulated Amortization |  | Net Amount
Intangible assets subject to amortization: |  |  |  |  |  |  |  |  |  |  |
Trade name | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | 1.1 |  |  | $ | (0.6 | ) |  | $ | 0.5 |
Software programs/platforms | 2.7 |  |  | (2.5 | ) |  | 0.2 |  |  | 2.7 |  |  | (2.4 | ) |  | 0.3 |
Customer base | 20.0 |  |  | (7.9 | ) |  | 12.1 |  |  | 14.0 |  |  | (5.7 | ) |  | 8.3 |
Total intangible assets | $ | 22.7 |  |  | $ | (10.4 | ) |  | $ | 12.3 |  |  | $ | 17.8 |  |  | $ | (8.7 | ) |  | $ | 9.1 |
Amortization expense related to intangible assets was $2.8 million, $1.6 million, and $1.5 million for the fiscal years ended September 30, 2017, 2016, and 2015, respectively. The estimated future amortization expense as of September 30, 2017 is as follows (in millions):
Year ending September 30, |
2018 | $ | 2.2 |
2019 | 2.2 |
2020 | 2.0 |
2021 | 1.9 |
2022 and thereafter | 4.0 |
| $ | 12.3 |

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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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