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Description of Business and Significant Accounting Policies - Accounting Standards Adopted (Details) $ in Millions | 12 Months Ended
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Sep. 30, 2018 USD ($)
Accounting Policies Adopted [Abstract] |
Excess Tax Benefit from Share-based Compensation, Operating Activities | $ 0.5

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- Definition Accounting Policies Adopted [Abstract] + References No definition available. + Details
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- Definition Amount of cash outflow for realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 20 -Section 55 -Paragraph 24 -URI http://asc.fasb.org/extlink&oid=96864182&loc=d3e11374-113907 + Details
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