Balance Sheet Components (Summary of Available-for-sale Investments and Restricted Cash) (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025	Mar. 31, 2025
Debt Securities, Available-for-Sale [Line Items]
Debt Securities, Available-for-Sale, Amortized Cost, Total	$ 241,641	$ 267,736
Gross Unrealized Gains	1	169
Gross Unrealized Losses	(365)	(15)
Cash equivalents	1,348	27,806
Short-term investments	138,645	132,010
Long-term investments	96,582	103,365
Restricted cash	4,702	4,709	$ 4,475
Estimated Fair Value	241,277	267,890
Money Market Funds Included In Cash Equivalents [Member]
Debt Securities, Available-for-Sale [Line Items]
Debt Securities, Available-for-Sale, Amortized Cost, Total	1,348	27,806
Estimated Fair Value	1,348	27,806
Money Market Funds Included In Restricted Cash, Noncurrent [Member]
Debt Securities, Available-for-Sale [Line Items]
Debt Securities, Available-for-Sale, Amortized Cost, Total	4,702	4,709
Estimated Fair Value	4,702	4,709
U.S. Government Securities [Member]
Debt Securities, Available-for-Sale [Line Items]
Debt Securities, Available-for-Sale, Amortized Cost, Total	81,500	81,385
Gross Unrealized Gains		94
Gross Unrealized Losses	(78)
Estimated Fair Value	81,422	81,479
U.S. Treasury Bills [Member]
Debt Securities, Available-for-Sale [Line Items]
Debt Securities, Available-for-Sale, Amortized Cost, Total	19,864	39,568
Gross Unrealized Gains	1	25
Estimated Fair Value	19,865	39,593
Corporate Bonds/Notes [Member]
Debt Securities, Available-for-Sale [Line Items]
Debt Securities, Available-for-Sale, Amortized Cost, Total	63,517	57,564
Gross Unrealized Gains		19
Gross Unrealized Losses	(153)	(12)
Estimated Fair Value	63,364	57,571
Agency Bonds/Notes [Member]
Debt Securities, Available-for-Sale [Line Items]
Debt Securities, Available-for-Sale, Amortized Cost, Total	44,137	25,147
Gross Unrealized Gains		7
Gross Unrealized Losses	(108)	(3)
Estimated Fair Value	44,029	25,151
Asset-Backed Securities [Member]
Debt Securities, Available-for-Sale [Line Items]
Debt Securities, Available-for-Sale, Amortized Cost, Total	21,638	21,689
Gross Unrealized Gains		22
Gross Unrealized Losses	(25)
Estimated Fair Value	21,613	21,711
Commercial Paper [Member]
Debt Securities, Available-for-Sale [Line Items]
Debt Securities, Available-for-Sale, Amortized Cost, Total	4,935	9,868
Gross Unrealized Gains		2
Gross Unrealized Losses	(1)
Estimated Fair Value	$ 4,934	$ 9,870

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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