Employee Stock Option Program (EOP), Authorized Shares

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Payout Percent

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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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.

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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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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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

+ References

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- Definition

Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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- Definition

Amount of cost expensed and capitalized for award under share-based payment arrangement.

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- Definition

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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- Definition

Number of new stock issued during the period.

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Stock-Based Compensation - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended			48 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2019	Sep. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of common stock reserved for issuance under plan (in shares)	1,700,000			1,700,000
Number of shares of common stock available for future grants (in shares)	1,200,000			1,200,000
Intrinsic value of stock options exercisable	$ 1.1			$ 1.1
Intrinsic value of stock options vested and expected to vest	1.0			1.0
Intrinsic value of stock options outstanding	$ 0.9			$ 0.9
Employee stock option program (EOP), authorized shares (in shares)	100,000			100,000
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average period to recognize remaining cost	1 year 1 month 25 days
Unrecognized compensation cost	$ 0.1	$ 0.2		$ 0.1
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards granted in period (in shares)	30,782
Employee purchase plan (EOP)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	2 years
Performance-based restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance share awards to be vested	778,814	644,785	668,766	778,814	448,693
Estimated fair value of nonvested stock (in dollars per share)	$ 9.95	$ 22.40	$ 13.60
Performance-based restricted stock \| 2019 Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards granted in period (in shares)	381,769
Performance share awards to be vested	390,043			390,043
Compensation cost related to performance based awards	$ 2.7	$ 2.0	$ 1.0	$ 5.9
Unrecognized compensation cost	$ 0.2			$ 0.2
Award vesting period	3 years
Performance-based restricted stock \| 2019 Performance Shares \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payout percentage	0.00%
Performance-based restricted stock \| 2019 Performance Shares \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payout percentage	175.00%
Total Shareholder Return Performance Share \| 2019 Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payout percentage	20.00%
Estimated fair value of nonvested stock (in dollars per share)	$ 10.50
Restricted stock awards expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average period to recognize remaining cost	1 year 8 months 1 day
Performance share awards to be vested	1,390,421	1,076,568	1,540,947	1,390,421	1,255,817
Unrecognized compensation cost	$ 9.0	$ 8.8		$ 9.0
Estimated fair value of nonvested stock (in dollars per share)	$ 9.89	$ 20.26	$ 13.04
Restricted stock awards expense \| 2016 Time-based Restricted Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards granted in period (in shares)	448,657