Fair Value Measurements - Fair Value of Financial Assets by Level (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2023	Dec. 31, 2022
Assets, Fair Value Disclosure [Abstract]
Cash Equivalents:	$ 709,525	$ 709,525	$ 397,261
Marketable Securities:	2,699,785	2,699,785	2,322,469
Marketable Securities	2,706,785	2,706,785	2,352,022
Total Financial Assets	3,417,168	3,417,168	2,753,554
Commercial paper
Assets, Fair Value Disclosure [Abstract]
Marketable Securities:	27,764	27,764	0
Certificates of deposits
Assets, Fair Value Disclosure [Abstract]
Marketable Securities:	7,000	7,000	10,492
U.S. government notes
Assets, Fair Value Disclosure [Abstract]
Marketable Securities:	901,551	901,551	993,955
Corporate bonds
Assets, Fair Value Disclosure [Abstract]
Marketable Securities:	1,125,203	1,125,203	1,113,134
Agency securities
Assets, Fair Value Disclosure [Abstract]
Marketable Securities:	645,267	645,267	215,380
Marketable equity securities
Assets, Fair Value Disclosure [Abstract]
Marketable equity securities	0	0	19,061
Proceeds from sale of marketable equity securities	23,900
Realized loss on equity investment	1,000
Unrealized gain on equity investment		5,800
Initial cost for equity investment	3,000	3,000
Cumulative gain from initial purchase of equity investment	20,900	20,900
Money market funds - restricted
Assets, Fair Value Disclosure [Abstract]
Money market funds - restricted	858	858	4,271
Money market funds
Assets, Fair Value Disclosure [Abstract]
Cash Equivalents:	709,525	709,525	322,294
Commercial paper
Assets, Fair Value Disclosure [Abstract]
Cash Equivalents:	0	0	5,422
U.S. government notes
Assets, Fair Value Disclosure [Abstract]
Cash Equivalents:	0	0	51,986
Agency securities
Assets, Fair Value Disclosure [Abstract]
Cash Equivalents:	0	0	17,559
Level I
Assets, Fair Value Disclosure [Abstract]
Cash Equivalents:	709,525	709,525	374,280
Marketable Securities	901,551	901,551	1,013,016
Total Financial Assets	1,611,934	1,611,934	1,391,567
Level I \| Commercial paper
Assets, Fair Value Disclosure [Abstract]
Marketable Securities:	0	0	0
Level I \| Certificates of deposits
Assets, Fair Value Disclosure [Abstract]
Marketable Securities:	0	0	0
Level I \| U.S. government notes
Assets, Fair Value Disclosure [Abstract]
Marketable Securities:	901,551	901,551	993,955
Level I \| Corporate bonds
Assets, Fair Value Disclosure [Abstract]
Marketable Securities:	0	0	0
Level I \| Agency securities
Assets, Fair Value Disclosure [Abstract]
Marketable Securities:	0	0	0
Level I \| Marketable equity securities
Assets, Fair Value Disclosure [Abstract]
Marketable equity securities	0	0	19,061
Level I \| Money market funds - restricted
Assets, Fair Value Disclosure [Abstract]
Money market funds - restricted	858	858	4,271
Level I \| Money market funds
Assets, Fair Value Disclosure [Abstract]
Cash Equivalents:	709,525	709,525	322,294
Level I \| Commercial paper
Assets, Fair Value Disclosure [Abstract]
Cash Equivalents:	0	0	0
Level I \| U.S. government notes
Assets, Fair Value Disclosure [Abstract]
Cash Equivalents:	0	0	51,986
Level I \| Agency securities
Assets, Fair Value Disclosure [Abstract]
Cash Equivalents:	0	0	0
Level II
Assets, Fair Value Disclosure [Abstract]
Cash Equivalents:	0	0	22,981
Marketable Securities	1,805,234	1,805,234	1,339,006
Total Financial Assets	1,805,234	1,805,234	1,361,987
Level II \| Commercial paper
Assets, Fair Value Disclosure [Abstract]
Marketable Securities:	27,764	27,764	0
Level II \| Certificates of deposits
Assets, Fair Value Disclosure [Abstract]
Marketable Securities:	7,000	7,000	10,492
Level II \| U.S. government notes
Assets, Fair Value Disclosure [Abstract]
Marketable Securities:	0	0	0
Level II \| Corporate bonds
Assets, Fair Value Disclosure [Abstract]
Marketable Securities:	1,125,203	1,125,203	1,113,134
Level II \| Agency securities
Assets, Fair Value Disclosure [Abstract]
Marketable Securities:	645,267	645,267	215,380
Level II \| Marketable equity securities
Assets, Fair Value Disclosure [Abstract]
Marketable equity securities	0	0	0
Level II \| Money market funds - restricted
Assets, Fair Value Disclosure [Abstract]
Money market funds - restricted	0	0	0
Level II \| Money market funds
Assets, Fair Value Disclosure [Abstract]
Cash Equivalents:	0	0	0
Level II \| Commercial paper
Assets, Fair Value Disclosure [Abstract]
Cash Equivalents:	0	0	5,422
Level II \| U.S. government notes
Assets, Fair Value Disclosure [Abstract]
Cash Equivalents:	0	0	0
Level II \| Agency securities
Assets, Fair Value Disclosure [Abstract]
Cash Equivalents:	0	0	17,559
Level III
Assets, Fair Value Disclosure [Abstract]
Cash Equivalents:	0	0	0
Marketable Securities	0	0	0
Total Financial Assets	0	0	0
Level III \| Commercial paper
Assets, Fair Value Disclosure [Abstract]
Marketable Securities:	0	0	0
Level III \| Certificates of deposits
Assets, Fair Value Disclosure [Abstract]
Marketable Securities:	0	0	0
Level III \| U.S. government notes
Assets, Fair Value Disclosure [Abstract]
Marketable Securities:	0	0	0
Level III \| Corporate bonds
Assets, Fair Value Disclosure [Abstract]
Marketable Securities:	0	0	0
Level III \| Agency securities
Assets, Fair Value Disclosure [Abstract]
Marketable Securities:	0	0	0
Level III \| Marketable equity securities
Assets, Fair Value Disclosure [Abstract]
Marketable equity securities	0	0	0
Level III \| Money market funds - restricted
Assets, Fair Value Disclosure [Abstract]
Money market funds - restricted	0	0	0
Level III \| Money market funds
Assets, Fair Value Disclosure [Abstract]
Cash Equivalents:	0	0	0
Level III \| Commercial paper
Assets, Fair Value Disclosure [Abstract]
Cash Equivalents:	0	0	0
Level III \| U.S. government notes
Assets, Fair Value Disclosure [Abstract]
Cash Equivalents:	0	0	0
Level III \| Agency securities
Assets, Fair Value Disclosure [Abstract]
Cash Equivalents:	$ 0	$ 0	$ 0

Equity Securities, FV-NI, Cumulative Gain (Loss), Net

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of 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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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes 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.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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Cost of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Excludes equity method investment and investment in equity security without readily determinable fair value.

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Amount of realized gain (loss) from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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Amount of cash inflow from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as investing activity.

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