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Selected Balance Sheet Information: Accounts Receivable (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024	Sep. 30, 2024	Dec. 31, 2023
Selected Balance Sheet Information [Abstract]
Billed Accounts Receivable	$ 173.7	$ 201.5
Unbilled Revenue	79.8	151.8
Less: Allowance for Credit Losses	(2.1)	(2.1)	$ (1.4)	$ (2.2)
Account Receivable, net	$ 251.4	$ 351.2

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Selected Balance Sheet Information [Abstract]

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Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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Amount of allowance for credit loss on accounts receivable, classified as current.

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Amount received for services rendered and products shipped, but not yet billed, for non-contractual agreements due within one year or the normal operating cycle, if longer.

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