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Fair Value Measurements - Assets Measured at Fair Value On a Recurring Basis (Detail) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Debt Securities, Available-for-Sale	$ 707,109	$ 798,655
Cash equivalents
Cash Equivalents	160,150	71,237
Short-term
Debt Securities, Available-for-Sale	495,234	671,414
Long-term
Debt Securities, Available-for-Sale	51,725	56,004
Level 1
Debt Securities, Available-for-Sale	41,494	33,613
Level 1 | Cash equivalents
Cash Equivalents	41,494	33,613
Level 1 | Short-term
Debt Securities, Available-for-Sale	0	0
Level 1 | Long-term
Debt Securities, Available-for-Sale	0	0
Level 2
Debt Securities, Available-for-Sale	665,615	765,042
Level 2 | Cash equivalents
Cash Equivalents	118,656	37,624
Level 2 | Short-term
Debt Securities, Available-for-Sale	495,234	671,414
Level 2 | Long-term
Debt Securities, Available-for-Sale	51,725	56,004
US Government and agency obligations | Cash equivalents
Cash Equivalents	81,535	10,201
US Government and agency obligations | Short-term
Debt Securities, Available-for-Sale	94,295	208,648
US Government and agency obligations | Long-term
Debt Securities, Available-for-Sale	10,452	12,135
US Government and agency obligations | Level 1 | Cash equivalents
Cash Equivalents	0	0
US Government and agency obligations | Level 1 | Short-term
Debt Securities, Available-for-Sale	0	0
US Government and agency obligations | Level 1 | Long-term
Debt Securities, Available-for-Sale	0	0
US Government and agency obligations | Level 2 | Cash equivalents
Cash Equivalents	81,535	10,201
US Government and agency obligations | Level 2 | Short-term
Debt Securities, Available-for-Sale	94,295	208,648
US Government and agency obligations | Level 2 | Long-term
Debt Securities, Available-for-Sale	10,452	12,135
Money market funds | Cash equivalents
Cash Equivalents	41,494	33,613
Money market funds | Level 1 | Cash equivalents
Cash Equivalents	41,494	33,613
Money market funds | Level 2 | Cash equivalents
Cash Equivalents	0	0
Commercial paper | Cash equivalents
Cash Equivalents	22,689	19,575
Commercial paper | Short-term
Debt Securities, Available-for-Sale	149,807	237,870
Commercial paper | Level 1 | Cash equivalents
Cash Equivalents	0	0
Commercial paper | Level 1 | Short-term
Debt Securities, Available-for-Sale	0	0
Commercial paper | Level 2 | Cash equivalents
Cash Equivalents	22,689	19,575
Commercial paper | Level 2 | Short-term
Debt Securities, Available-for-Sale	149,807	237,870
Certificates of deposit | Short-term
Debt Securities, Available-for-Sale	7,239	0
Certificates of deposit | Level 1 | Short-term
Debt Securities, Available-for-Sale	0	0
Certificates of deposit | Level 2 | Short-term
Debt Securities, Available-for-Sale	7,239	0
Corporate debt securities | Cash equivalents
Cash Equivalents	4,133	0
Corporate debt securities | Short-term
Debt Securities, Available-for-Sale	242,313	210,982
Corporate debt securities | Long-term
Debt Securities, Available-for-Sale	39,931	43,869
Corporate debt securities | Level 1 | Cash equivalents
Cash Equivalents	0	0
Corporate debt securities | Level 1 | Short-term
Debt Securities, Available-for-Sale	0	0
Corporate debt securities | Level 1 | Long-term
Debt Securities, Available-for-Sale	0	0
Corporate debt securities | Level 2 | Cash equivalents
Cash Equivalents	4,133	0
Corporate debt securities | Level 2 | Short-term
Debt Securities, Available-for-Sale	242,313	210,982
Corporate debt securities | Level 2 | Long-term
Debt Securities, Available-for-Sale	39,931	43,869
Municipal debt securities | Cash equivalents
Cash Equivalents	10,299	7,848
Municipal debt securities | Short-term
Debt Securities, Available-for-Sale	1,580	13,914
Municipal debt securities | Long-term
Debt Securities, Available-for-Sale	1,342	0
Municipal debt securities | Level 1 | Cash equivalents
Cash Equivalents	0	0
Municipal debt securities | Level 1 | Short-term
Debt Securities, Available-for-Sale	0	0
Municipal debt securities | Level 1 | Long-term
Debt Securities, Available-for-Sale	0	0
Municipal debt securities | Level 2 | Cash equivalents
Cash Equivalents	10,299	7,848
Municipal debt securities | Level 2 | Short-term
Debt Securities, Available-for-Sale	1,580	13,914
Municipal debt securities | Level 2 | Long-term
Debt Securities, Available-for-Sale	$ 1,342	$ 0

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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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