Balance Sheet Components (Fair Value of Available-For-Sale Investments) (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 197,461	$ 213,641
Gross Unrealized Gains	1	14
Gross Unrealized Losses	(285)	(181)
Estimated Fair Value	197,177	213,474
Cash equivalents	29,156	55,158
Short-term investments	163,673	158,316
Long-term Investments	4,348
Total	197,177	213,474
Money Market Funds [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	29,156	55,158
Estimated Fair Value	29,156	55,158
US Treasury Bills [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	7,844	19,772
Gross Unrealized Gains		4
Estimated Fair Value	7,844	19,776
Commercial Paper [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	38,689	48,875
Estimated Fair Value	38,689	48,875
Corporate Bonds/Notes [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	34,110	1,528
Gross Unrealized Losses	(93)	(13)
Estimated Fair Value	34,017	1,515
U.S. Government Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	7,991	83,432
Gross Unrealized Gains		2
Gross Unrealized Losses	(1)	(164)
Estimated Fair Value	7,990	83,270
Asset-Backed Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		2,000
Gross Unrealized Losses		(4)
Estimated Fair Value		1,996
Agency bonds/notes [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	79,671	2,876
Gross Unrealized Gains	1	8
Gross Unrealized Losses	(191)
Estimated Fair Value	$ 79,481	$ 2,884

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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