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Sale of Stock, Shares Registered for Resale

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Aggregate number of common shares reserved for future issuance.

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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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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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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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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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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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Amount of stock repurchase plan authorized.

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Amount remaining of a stock repurchase plan authorized.

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Cumulative amount of cash and other consideration received by subsidiary or equity method investee in exchange for shares or stock issued or sold. Include amounts of cash received, fair value of non-cash assets received, fair value of liabilities assumed, and fair value of any other forms of consideration.

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Number of shares that have been repurchased during the period and are being held in treasury.

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Stockholders’ Equity - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions			3 Months Ended		12 Months Ended
	May 30, 2022	Sep. 30, 2014	Jun. 30, 2023	Jun. 30, 2022	Mar. 31, 2023	Sep. 30, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares repurchased (in shares)			0	56,000
Stock repurchase program, authorized amount						$ 50.0
Stock repurchase program, remaining repurchase amount			$ 26.8
Shares issued on conversion (in shares)	500,000
Common Class B \| Pdv Spectrum Holding Company Llc
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity method investee, cumulative proceeds received on all transactions		$ 10.0
Sale of stock (in shares)		500,000
Sale of stock (in dollars per share)		$ 20.00
Common Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of units owned		100.00%
Shares registered for resale (in shares)				500,000
Common Class A \| Pdv Spectrum Holding Company Llc
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Subsidiary equity units for which investor has right to convert to common stock (in shares)		500,000
2014 Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock authorized and reserved for issuance (in shares)			5,027,201
Shares available (in shares)			489,638
Awards issued (in shares)			125,160		260,370
2014 Stock Plan \| Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock authorized and reserved for issuance (in shares)			142,549