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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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Exercise price per share or per unit of warrants or rights outstanding.

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Number of warrants or rights outstanding.

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Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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Aggregate amount of redemption requirements for each class or type of redeemable stock classified as temporary equity for each of the five years following the latest balance sheet date. The redemption requirement does not constitute an unconditional obligation that will be settled in a variable number of shares constituting a monetary value predominantly indexed to (a) a fixed monetary amount known at inception, (b) an amount inversely correlated with the residual value of the entity, or (c) an amount determined by reference to something other than the fair value of issuer's stock. Does not include mandatorily redeemable stock. The exception is if redemption is required upon liquidation or termination of the reporting entity.

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Accretion of temporary equity during the period due to cash, stock, and in-kind dividends. This item is an adjustment to net income necessary to derive net income apportioned to common stockholders and is to be distinguished from Temporary Equity, Accretion of Dividends (Temporary Equity, Accretion of Dividends).

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The number of securities classified as temporary equity that have been sold (or granted) to the entity's shareholders. Securities issued include securities outstanding and securities held in treasury. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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The number of securities classified as temporary equity that have been issued and are held by the entity's shareholders. Securities outstanding equals securities issued minus securities held in treasury. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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Value of outstanding derivative securities that permit the holder the right to purchase securities (usually equity) from the issuer at a specified price.

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Stockholders' / Members' Equity and Redeemable Class A Units (Details) - USD ($) $ / shares in Units, $ in Thousands			12 Months Ended
	Jun. 10, 2019	Jun. 25, 2018	Sep. 30, 2017	Sep. 30, 2019	Sep. 30, 2018
Class of Stock [Line Items]
Preferred Stock authorized (shares)		10,000,000		10,000,000	10,000,000
Preferred Stock, par value (in USD per share)		$ 0.0001		$ 0.0001	$ 0.0001
Mezzanine Warrants
Class of Stock [Line Items]
Warrants outstanding (shares)			1,423,688
IPO
Class of Stock [Line Items]
Shares issued (shares)		7,647,500
Unsecured Debt \| Junior Subordinated Notes
Class of Stock [Line Items]
Warrants outstanding (shares)			1,433,920
Intrinsic value of warrants			$ 0
Warrant exercise price (in USD per share)			$ 2.095
Class A Common Stock
Class of Stock [Line Items]
Common Stock authorized (shares)		150,000,000		150,000,000	150,000,000
Common Stock, par value (in USD per share)		$ 0.0001		$ 0.0001	$ 0.0001
Shares issued (shares)	5,165,527
Units issued (shares)			13,892,129
Units outstanding (shares)			13,892,129
Cumulative preferred return		$ 7,627			$ 5,105
Distributions to unit holders			$ 625
Common Stock issued (shares)				14,444,115	9,112,042
Common Stock, outstanding (shares)				14,444,115	9,112,042
Class B Common Stock
Class of Stock [Line Items]
Common Stock authorized (shares)		40,000,000		40,000,000	40,000,000
Common Stock, par value (in USD per share)		$ 0.0001		$ 0.0001	$ 0.0001
Common Stock issued (shares)				12,921,637	17,213,806
Common Stock, outstanding (shares)				12,921,637	17,213,806
Redeemable Class A Units
Class of Stock [Line Items]
Units issued (shares)			4,900,000
Units outstanding (shares)			4,900,000
Annual preferred return rate (percent)			10.00%
Cumulative preferred return		$ 3,376			$ 2,823
Distributions to unit holders			$ 131
Common Stock
Class of Stock [Line Items]
Common Stock issued (shares)			1,548,722
Common Stock, outstanding (shares)			1,548,722
Restricted Class P Units
Class of Stock [Line Items]
Common Stock issued (shares)			7,647,350
Common Stock, outstanding (shares)			7,647,350