Stockholders' Equity - Narrative (Details)	12 Months Ended
Sep. 30, 2019 item shares
Stockholders' Equity
Retirement age for participants	60 years
Retirement age and years of service combined	70 years
Notice period	1 year
RSUs
Stockholders' Equity
Number of shares of common stock that each award holder has the contingent right to receive	1
Time-based RSUs
Stockholders' Equity
Number of equal installments for vesting of stock awards \| item	4
Expected awards vested (in shares)	366,913
Performance-based RSUs
Stockholders' Equity
Vesting period	3 years
Expected awards vested (in shares)	112,942
Performance and market-based RSUs
Stockholders' Equity
Number of shares of common stock that each award holder has the contingent right to receive	1.25
Vesting period	3 years
Expected awards vested (in shares)	174,105
Performance and market-based RSUs \| Maximum
Stockholders' Equity
Increase (decrease) in multiplier based on performance	25.00%
Performance and market-based RSUs \| Minimum
Stockholders' Equity
Increase (decrease) in multiplier based on performance	(25.00%)

The percentage in increase in multiplier based on performance.

No definition available.

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- Definition

Notice period by the Participants who have reached the retirement age criteria provide notice of retirement to the Company, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

The age of participant in the long-term equity incentive program to provide accelerated vesting for retirement age participants in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Estimated period over which an employee is required to provide service and retirement age combined to get accelerated vesting under long-term equity incentive program, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Represents the number of shares of common stock that each award holder has the contingent right to receive.

+ References

No definition available.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that are expected to vest during the reporting period.

+ References

No definition available.

+ Details

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- Definition

Represents the number of equal installments for vesting of share-based compensation awards.

+ References

No definition available.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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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.

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