Fair Value Measurements - Additional Information (Details) $ in Millions	9 Months Ended	12 Months Ended
Sep. 30, 2025 USD ($) ForwardStartingSwap	Dec. 31, 2024 USD ($)
Derivative [Line Items]
Unrealized gain (loss) on interest rate cash flow hedges, pretax, accumulated other comprehensive income (loss)	$ 1.9	$ 4.2
Interest rate cash flow hedge gain (loss) to be reclassified during next 12 months, net	1.1
Proceeds from sale of portion of investment securities	0.4
Unrealized gain on sale of investment securities	25.4
Unsecured - Public [Member]
Derivative [Line Items]
Notes issued	$ 500.0
Notes, term	7 years
Interest expense	$ 2.3
Forward Starting Swaps [Member]
Derivative [Line Items]
Amount paid to settle forward starting swaps	$ 3.5
Number of forward starting swaps settled \| ForwardStartingSwap	5
Repayment of future note	$ 1.2
Derivative, term	10 years

Number of forward starting swaps settled.

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Amount of gain from upward price adjustment on investment in equity security without readily determinable fair value.

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Amount of interest expense classified as operating and nonoperating. Includes, but is not limited to, cost of borrowing accounted for as interest expense.

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The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

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The cash outflow for a financial contract that meets the hedge criteria as either cash flow hedge, fair value hedge or hedge of net investment in foreign operations.

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Amount of unrealized gain (loss) related to the increase or decrease in fair value of interest rate derivatives designated as cash flow hedging instruments, which was recorded in accumulated other comprehensive income to the extent that the cash flow hedge was determined to be effective.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

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