Marketable Securities (Schedule of Amortized Cost Basis and Fair Value of Available-for-Sale Marketable Securities) (Details) $ in Millions	Sep. 30, 2023 USD ($)
Amortized Cost
Less than 1 year	$ 15.8
1 to 2 years	0.0
Amortized Cost	15.8
Fair Value
Less than 1 year	15.8
1 to 2 years	0.0
Fair Value	$ 15.8

Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, Year Two

No definition available.

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- Definition

Debt Securities, Available-for-Sale Excluding Cash And Cash Equivalents

+ References

No definition available.

+ Details

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- Definition

Debt Securities, Available-for-Sale Excluding Cash And Cash Equivalents, Amortized Cost

+ References

No definition available.

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- Definition

Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, Year Two

+ References

No definition available.

+ Details

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- References

No definition available.

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- References

No definition available.

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- Definition

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

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- Definition

Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 320
-Name Accounting Standards Codification
-Section 50
-Paragraph 3A
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480832/942-320-50-3A

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