Fair Value of Financial Instruments (Schedule of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis) (Details) - USD ($)	Sep. 30, 2026	Dec. 31, 2025
Debt Securities [Abstract]
Total assets at fair value	$ 0	$ 0
Short-term investments
Debt Securities [Abstract]
Debt securities	151,000,000	28,000,000
Corporate debt securities
Debt Securities [Abstract]
Debt securities	100,000,000	0
Fair value, recurring
Debt Securities [Abstract]
Debt securities		28,000,000
Equity securities	10,000,000	25,000,000
Total assets at fair value	261,000,000	53,000,000
Fair value, recurring \| Level 1
Debt Securities [Abstract]
Debt securities		28,000,000
Equity securities	10,000,000	25,000,000
Total assets at fair value	161,000,000	53,000,000
Fair value, recurring \| Level 2
Debt Securities [Abstract]
Debt securities		0
Equity securities	0	0
Total assets at fair value	0	0
Fair value, recurring \| Level 3
Debt Securities [Abstract]
Debt securities		0
Equity securities	0	0
Total assets at fair value	100,000,000	0
Fair value, recurring \| Short-term investments
Debt Securities [Abstract]
Debt securities	151,000,000
Fair value, recurring \| Short-term investments \| Level 1
Debt Securities [Abstract]
Debt securities	151,000,000
Fair value, recurring \| Short-term investments \| Level 2
Debt Securities [Abstract]
Debt securities	0
Fair value, recurring \| Short-term investments \| Level 3
Debt Securities [Abstract]
Debt securities	0
Fair value, recurring \| European government debt securities
Debt Securities [Abstract]
Debt securities	151,000,000	28,000,000
Fair value, recurring \| European government debt securities \| Level 1
Debt Securities [Abstract]
Debt securities	151,000,000	28,000,000
Fair value, recurring \| European government debt securities \| Level 2
Debt Securities [Abstract]
Debt securities	0	0
Fair value, recurring \| European government debt securities \| Level 3
Debt Securities [Abstract]
Debt securities	0	$ 0
Fair value, recurring \| Corporate debt securities
Debt Securities [Abstract]
Debt securities	100,000,000
Fair value, recurring \| Corporate debt securities \| Level 1
Debt Securities [Abstract]
Debt securities	0
Fair value, recurring \| Corporate debt securities \| Level 2
Debt Securities [Abstract]
Debt securities	0
Fair value, recurring \| Corporate debt securities \| Level 3
Debt Securities [Abstract]
Debt securities	$ 100,000,000