Senior Notes and Other Long-Term Debt - Senior Notes (Detail) - USD ($) $ in Millions |
3 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
Sep. 30, 2024 |
Sep. 28, 2023 |
Jun. 30, 2026 |
Jun. 30, 2025 |
Mar. 31, 2025 |
Sep. 25, 2024 |
May 30, 2023 |
Jun. 30, 2020 |
Mar. 31, 2019 |
Sep. 30, 2017 |
|
| 2031 Notes [Member] | ||||||||||
| Debt Instrument [Line Items] | ||||||||||
| Principal amount of senior notes issued | $ 733.4 | |||||||||
| Debt maturity year | 2031 | |||||||||
| Interest rate on the outstanding borrowings | 7.50% | |||||||||
| 2031 Notes [Member] | Debt Instrument, Redemption, Period Two [Member] | ||||||||||
| Debt Instrument [Line Items] | ||||||||||
| Redemption description of Senior Notes | The 2031 Notes may be redeemed, in whole or in part, at any time during the 12 months beginning on May 30, 2026 at a redemption price of 103.750% | |||||||||
| Redemption price percentage of Senior Notes | 103.75% | |||||||||
| 2031 Notes [Member] | Debt Instrument, Redemption, Period Three [Member] | ||||||||||
| Debt Instrument [Line Items] | ||||||||||
| Redemption description of Senior Notes | during the 12 months beginning on May 30, 2027 at a redemption price of 101.875% | |||||||||
| Redemption price percentage of Senior Notes | 101.875% | |||||||||
| 2031 Notes [Member] | Debt Instrument, Redemption, Period Four [Member] | ||||||||||
| Debt Instrument [Line Items] | ||||||||||
| Redemption description of Senior Notes | at any time on or after May 30, 2028 at a redemption price of 100%, in each case plus accrued and unpaid interest, if any, thereon to the redemption date. | |||||||||
| Redemption price percentage of Senior Notes | 100.00% | |||||||||
| 2031 Notes [Member] | Change of Control [Member] | ||||||||||
| Debt Instrument [Line Items] | ||||||||||
| Redemption description of Senior Notes | In the event a change of control triggering event occurs (as defined in the indenture governing the 2031 Notes), each holder will have the right to require the Company to repurchase all or any part of such holder’s 2031 Notes at a purchase price in cash equal to 101% of the aggregate principal amount of the 2031 Notes repurchased, plus accrued and unpaid interest, if any, to the date of purchase (subject to the right of holders of record on the relevant record date to receive interest due on the relevant interest payment date). | |||||||||
| Redemption price percentage of Senior Notes | 101.00% | |||||||||
| 2028 Notes [Member] | ||||||||||
| Debt Instrument [Line Items] | ||||||||||
| Principal amount of senior notes issued | $ 400.0 | |||||||||
| Debt maturity year | 2028 | |||||||||
| Interest rate on the outstanding borrowings | 6.50% | |||||||||
| 2028 Notes [Member] | Debt Instrument, Redemption, Other Period One [Member] | ||||||||||
| Debt Instrument [Line Items] | ||||||||||
| Redemption description of Senior Notes | in whole or in part, at any time at a redemption price of 100% plus accrued and unpaid interest, if any, thereon to the redemption date. | |||||||||
| 2028 Notes [Member] | Debt Instrument, Redemption, Period Two [Member] | ||||||||||
| Debt Instrument [Line Items] | ||||||||||
| Redemption price percentage of Senior Notes | 100.00% | |||||||||
| 2028 Notes [Member] | Change of Control [Member] | ||||||||||
| Debt Instrument [Line Items] | ||||||||||
| Redemption description of Senior Notes | In the event a change of control triggering event occurs (as defined in the indenture governing the 2028 Notes), each holder will have the right to require the Company to repurchase all or any part of such holder’s 2028 Notes at a purchase price in cash equal to 101% of the aggregate principal amount of the 2028 Notes repurchased, plus accrued and unpaid interest, if any, to the date of purchase (subject to the right of holders of record on the relevant record date to receive interest due on the relevant interest payment date). | |||||||||
| Redemption price percentage of Senior Notes | 101.00% | |||||||||
| 2027 Notes [Member] | ||||||||||
| Debt Instrument [Line Items] | ||||||||||
| Principal amount of senior notes issued | $ 600.0 | |||||||||
| Debt maturity year | 2027 | |||||||||
| Interest rate on the outstanding borrowings | 5.625% | |||||||||
| 2027 Notes [Member] | Debt Instrument, Redemption, Period One [Member] | ||||||||||
| Debt Instrument [Line Items] | ||||||||||
| Redemption description of Senior Notes | in whole or in part, at any time at a redemption price of 100% plus accrued and unpaid interest, if any, thereon to the redemption date. | |||||||||
| Redemption price percentage of Senior Notes | 100.00% | |||||||||
| 2027 Notes [Member] | Change of Control [Member] | ||||||||||
| Debt Instrument [Line Items] | ||||||||||
| Redemption description of Senior Notes | In the event a change of control triggering event occurs (as defined in the indenture governing the 2027 Notes), each holder will have the right to require the Company to repurchase all or any part of such holder’s 2027 Notes at a purchase price in cash equal to 101% of the aggregate principal amount of the 2027 Notes repurchased, plus accrued and unpaid interest, if any, to the date of purchase (subject to the right of holders of record on the relevant record date to receive interest due on the relevant interest payment date). | |||||||||
| Redemption price percentage of Senior Notes | 101.00% | |||||||||
| 2025 Notes [Member] | ||||||||||
| Debt Instrument [Line Items] | ||||||||||
| Principal amount of senior notes issued | $ 700.0 | |||||||||
| Debt maturity year | 2025 | |||||||||
| Principal amount of senior notes repurchased | $ 442.6 | $ 257.5 | ||||||||
| Interest rate on the outstanding borrowings | 5.625% | |||||||||
| Redemption price percentage of Senior Notes | 100.00% | |||||||||
| Inmarsat Senior Secured Notes 2029 [Member] | ||||||||||
| Debt Instrument [Line Items] | ||||||||||
| Principal amount of senior notes issued | $ 1,975.0 | |||||||||
| Debt maturity year | 2029 | |||||||||
| Interest rate on the outstanding borrowings | 9.00% | |||||||||
| Inmarsat Senior Secured Notes 2029 [Member] | Debt Instrument, Redemption, Other Period One [Member] | ||||||||||
| Debt Instrument [Line Items] | ||||||||||
| Redemption description of Senior Notes | The issuers may also redeem the Inmarsat 2029 Notes prior to September 15, 2026, in whole or in part, at a redemption price equal to 100% of the principal amount thereof plus a “make-whole” premium and any accrued and unpaid interest, if any, thereon to the redemption date. | |||||||||
| Redemption price percentage of Senior Notes | 100.00% | |||||||||
| Inmarsat Senior Secured Notes 2029 [Member] | Debt Instrument, Redemption, Period One [Member] | ||||||||||
| Debt Instrument [Line Items] | ||||||||||
| Redemption description of Senior Notes | Prior to September 15, 2026, the issuers may redeem up to 40% of the Inmarsat 2029 Notes at a redemption price 109.000% of the principal amount thereof, plus accrued and unpaid interest, if any, thereon to the redemption date, from the net cash proceeds of specified equity offerings so long as at least 50% of the aggregate principal amount of the Inmarsat 2029 Notes originally issued remains outstanding after such redemptions. | |||||||||
| Redemption price percentage of Senior Notes | 109.00% | |||||||||
| Inmarsat Senior Secured Notes 2029 [Member] | Debt Instrument, Redemption, Period Two [Member] | ||||||||||
| Debt Instrument [Line Items] | ||||||||||
| Redemption description of Senior Notes | The Inmarsat 2029 Notes may be redeemed, in whole or in part, at any time during the 12 months beginning on September 15, 2026 at a redemption price of 104.500% | |||||||||
| Redemption price percentage of Senior Notes | 104.50% | |||||||||
| Inmarsat Senior Secured Notes 2029 [Member] | Debt Instrument, Redemption, Period Three [Member] | ||||||||||
| Debt Instrument [Line Items] | ||||||||||
| Redemption description of Senior Notes | during the 12 months beginning on September 15, 2027 at a redemption price of 102.250% | |||||||||
| Redemption price percentage of Senior Notes | 102.25% | |||||||||
| Inmarsat Senior Secured Notes 2029 [Member] | Debt Instrument, Redemption, Period Four [Member] | ||||||||||
| Debt Instrument [Line Items] | ||||||||||
| Redemption description of Senior Notes | at any time on or after September 15, 2028 at a redemption price of 100%, in each case plus accrued and unpaid interest, if any, thereon to the redemption date. | |||||||||
| Redemption price percentage of Senior Notes | 100.00% | |||||||||
| Inmarsat Senior Secured Notes 2029 [Member] | Change of Control [Member] | ||||||||||
| Debt Instrument [Line Items] | ||||||||||
| Redemption description of Senior Notes | In the event a change of control occurs (as defined in the indenture governing the Inmarsat 2029 Notes), each holder will have the right to require the issuers to repurchase all or a portion of such holder’s Inmarsat 2029 Notes at a purchase price in cash equal to 101% of the aggregate principal amount of the Inmarsat 2029 Notes repurchased, plus accrued and unpaid interest, if any, to the date of purchase (subject to the right of holders of record on the relevant record date to receive interest due on the relevant interest payment date). | |||||||||
| Redemption price percentage of Senior Notes | 101.00% | |||||||||
| Bridge Facility [Member] | ||||||||||
| Debt Instrument [Line Items] | ||||||||||
| Credit Facility maximum borrowing capacity | $ 733.4 | |||||||||