At-the-market Equity Offering Program, Common Stock Available for Issuance

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- Definition

At-the-market Equity Offering Program, Common Stock Issued

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At-the-market Equity Offering Program, Net Proceeds

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Common Stock Available for Issuance, Value Remaining

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The dollar amount of equity securities registered under the entity's registration statement.

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Amount of decrease in additional paid in capital (APIC) resulting from direct costs associated with issuing stock. Includes, but is not limited to, legal and accounting fees and direct costs associated with stock issues under a shelf registration.

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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.

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Amount of noncash expense for share-based payment arrangement.

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The number of grants made 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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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Nov. 18, 2021	Oct. 08, 2021
Class of Stock [Line Items]
Equity Securities Registered, Value						$ 750.0
At-the-market Equity Offering Program, Common Stock Available for Issuance	$ 298.2		$ 298.2		$ 300.0
At-the-market Equity Offering Program, Common Stock Issued	0		84,547
At-the-market Equity Offering Program, Net Proceeds			$ 1.7
Adjustments to Additional Paid in Capital, Stock Issued, Issuance Costs			0.1
Common Stock Available for Issuance, Value Remaining	$ 748.2		$ 748.2
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	394,786
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value			$ 17.76
Stock-based compensation expense	$ 0.8	$ 0.8	$ 2.8	$ 2.0
Retirement Eligible
Class of Stock [Line Items]
Stock-based compensation expense			$ 1.2	$ 0.7