Stock-Based Compensation - Performance-Based Grants (Details) - Restricted Stock, Performance Based Shares	6 Months Ended	12 Months Ended
Mar. 31, 2018	Sep. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance-based awards granted, percentage, minimum (as a percent)		0.00%
Performance-based awards granted, percentage (as a percent)	100.00%	100.00%
Performance-based awards granted, percentage, maximum threshold met (as a percent)	200.00%	200.00%
Performance goal measurement period (in years)	3 years

- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Percentage of Performance-based Units Awarded, Financial Metric, Maximum Threshold Met.

+ References

No definition available.

+ Details

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Percentage of Performance-based Units Awarded, Financial Metric Target Met.

+ References

No definition available.

+ Details

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Percentage of Performance-based Units Awarded, Financial Metric Target Met, Minimum

+ References

No definition available.

+ Details

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Percentage of Performance-based Units Awarded, Measurement Period.

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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