Subsequent Event	6 Months Ended
Sep. 30, 2024
Subsequent Events [Abstract]
Subsequent Events	Note 12 — Subsequent Events In October 2024, subsequent to quarter end, Inmarsat used the net proceeds from the issuance of the Inmarsat 2029 Notes, together with cash on hand, to redeem all of the outstanding Inmarsat 2026 Notes at a redemption price of 100% of the principal amount so redeemed plus accrued and unpaid interest thereon to the redemption date, and the indenture governing the Inmarsat 2026 Notes was satisfied and discharged in accordance with its terms. As a result of the redemption of the Inmarsat 2026 Notes, the Company is expected to recognize a loss of approximately $97 million on extinguishment of debt during the third quarter of fiscal year 2025.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/855/tableOfContent

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483399/855-10-50-2

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