Financial Instruments (Cash, Cash Equivalents, and Marketable Securities) (Details) - USD ($) $ in Millions |
Sep. 30, 2026 |
Dec. 31, 2025 |
Sep. 30, 2025 |
Dec. 31, 2024 |
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| Debt Securities, Available-for-sale [Line Items] | ||||
| Cash | $ 16.0 | $ 18.5 | ||
| Time deposits | 2.1 | 1.9 | ||
| Money Market Funds (level 1) | 131.3 | 243.3 | ||
| Financial Instruments, Owned, US Government and Agency Obligations, at Fair Value | 328.3 | 318.4 | ||
| Total | 477.7 | 582.1 | ||
| Included in Cash and cash equivalents | 206.8 | 307.9 | ||
| Restricted Cash Equivalent, Noncurrent | 1.6 | 1.6 | ||
| Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents | 208.4 | 309.5 | $ 237.0 | $ 212.1 |
| Included in Marketable securities | $ 269.3 | $ 272.6 |
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- Definition Amount of cash and cash equivalent. Cash includes, but is not limited to, currency on hand, demand deposit with financial institution, and account with general characteristic of demand deposit. Cash equivalent includes, but is not limited to, short-term, highly liquid investment that is both readily convertible to known amount of cash and so near maturity that it presents insignificant risk of change in value because of change in interest rate. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the customer may deposit additional funds at any time and effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid Investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Short-term investments, exclusive of cash equivalents, generally consist of marketable securities intended to be sold within one year (or the normal operating cycle if longer) and may include trading securities, available-for-sale securities, or held-to-maturity securities (if maturing within one year), as applicable. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of cash and cash equivalent, and cash and cash equivalent restricted to withdrawal or usage; attributable to continuing operation. Cash includes, but is not limited to, currency on hand, demand deposit with financial institution, and account with general characteristic of demand deposit. Cash equivalent includes, but is not limited to, short-term, highly liquid investment that is both readily convertible to known amount of cash and so near maturity that it presents insignificant risk of change in value because of change in interest rate. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The fair value as of the balance sheet date of firm holdings in debt obligations issued by the US government including short-term Treasury bills, medium-term Treasury notes, and long-term Treasury bonds, as well as debt issued by agencies. Includes both pledged (to counterparties as collateral for financing transactions) and unpledged holdings. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of investment in marketable security, classified as current. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Investment in short-term money-market instruments (such as commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and so forth) which are highly liquid (that is, readily convertible to known amounts of cash) and so near their maturity that they present an insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify as cash equivalents by definition. Original maturity means an original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of cash equivalent restricted as to withdrawal or usage, classified as noncurrent. Cash equivalent includes, but is not limited to, short-term, highly liquid investment that is both readily convertible to known amount of cash and so near maturity that it presents insignificant risk of change in value because of change in interest rate. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Any certificate of deposit or savings account held by a bank or other financial institution for a short-term specified period of time. Because of their short-term, time deposits are considered highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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