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CAPITAL CONSTRUCTION FUND (Tables) | 9 Months Ended
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Sep. 30, 2025
CAPITAL CONSTRUCTION FUND |
Schedule of capital construction fund | ​
​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Nine Months Ended
​ | ​ | September 30,
(In millions) |  | 2025 |  | 2024
CCF Cash and Cash Equivalents: | ​ | ​ | ​ | ​ | ​ | ​
CCF cash and cash equivalents balance at beginning of period | ​ | $ | 230.7 | ​ | $ | 599.4
Cash deposits into the CCF | ​ | ​ | — | ​ | ​ | 50.0
Cash withdrawal for the purchase of U.S. Treasury debt securities and accrued interest | ​ | ​ | — | ​ | ​ | (449.8)
Proceeds from U.S. Treasury debt securities at maturity | ​ | ​ | 168.4 | ​ | ​ | —
Interest income on cash and cash equivalents, and CCF investments | ​ | ​ | 13.4 | ​ | ​ | 14.9
Repurchase of assigned accounts receivable | ​ | ​ | 100.7 | ​ | ​ | —
Qualifying withdrawal payments for vessel construction expenditures | ​ | ​ | (136.5) | ​ | ​ | (35.8)
Total CCF cash and cash equivalents balance at end of period | ​ | ​ | 376.7 | ​ | ​ | 178.7
​ | ​ | ​ | ​ | ​ | ​ | ​
CCF Investments: | ​ | ​ | ​ | ​ | ​ | ​
CCF investments balance at beginning of period | ​ | ​ | 411.9 | ​ | ​ | —
Purchase of U.S. Treasury debt securities | ​ | ​ | — | ​ | ​ | 448.1
Sale of U.S. Treasury debt securities at maturity | ​ | ​ | (168.4) | ​ | ​ | —
Accretion of investments | ​ | ​ | 7.7 | ​ | ​ | 8.6
Total CCF investments balance at end of period | ​ | ​ | 251.2 | ​ | ​ | 456.7
Total CCF cash and cash equivalents, and investments balance at end of period | ​ | $ | 627.9 | ​ | $ | 635.4
Schedule of maturities of capital construction fund investments | ​
​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | As of
​ | ​ | September 30, 2025
Year (in millions) |  | Cost | ​ | Fair Value
Remainder of 2025 | ​ | $ | 27.0 | ​ | $ | 27.0
2026 | ​ |  | 171.8 | ​ |  | 172.4
2027 | ​ |  | 52.4 | ​ |  | 52.8
Total CCF investments | ​ | $ | 251.2 | ​ | $ | 252.2

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