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Investments - Summary of Short-term and Long-term Investments and Marketable Securities (Detail) - USD ($) $ in Thousands | 1 Months Ended |  |
--- | --- | --- | ---
Apr. 30, 2022 | Jun. 30, 2022 | Sep. 30, 2021
Schedule Of Held To Maturity Securities And Marketable Securities [Line Items] |  |  |
Equity securities sold | $ 122,300 |  |
Total, Cost Basis |  | $ 468,302 | $ 429,703
Total, Gross Unrealized Gains |  | 32 | 1,954
Total, Gross Unrealized Losses |  | (7,968) | (856)
Total, Fair Value |  | 460,366 | 430,801
Commercial notes (due within one year) |  |  |
Schedule Of Held To Maturity Securities And Marketable Securities [Line Items] |  |  |
Held to Maturity, Cost Basis |  | 227,057 | 56,627
Held to Maturity, Gross Unrealized Gains |  | 21 | 803
Held to Maturity, Gross Unrealized Losses |  | (1,588) | 0
Held to Maturity, Fair Value |  | 225,490 | 57,430
Commercial notes (due within one through three years) |  |  |
Schedule Of Held To Maturity Securities And Marketable Securities [Line Items] |  |  |
Held to Maturity, Cost Basis |  | 165,920 | 195,595
Held to Maturity, Gross Unrealized Gains |  | 0 | 1,151
Held to Maturity, Gross Unrealized Losses |  | (6,380) | (103)
Held to Maturity, Fair Value |  | 159,540 | 196,643
Certificate of deposit (due within one through two years) |  |  |
Schedule Of Held To Maturity Securities And Marketable Securities [Line Items] |  |  |
Held to Maturity, Cost Basis |  |  | 50,000
Held to Maturity, Gross Unrealized Gains |  |  | 0
Held to Maturity, Gross Unrealized Losses |  |  | 0
Held to Maturity, Fair Value |  |  | 50,000
Certificate of deposit (due within one year) |  |  |
Schedule Of Held To Maturity Securities And Marketable Securities [Line Items] |  |  |
Held to Maturity, Cost Basis |  | 50,000 |
Held to Maturity, Gross Unrealized Gains |  | 0 |
Held to Maturity, Gross Unrealized Losses |  | 0 |
Held to Maturity, Fair Value |  | 50,000 |
Marketable securities |  |  |
Schedule Of Held To Maturity Securities And Marketable Securities [Line Items] |  |  |
Marketable Securities, Cost Basis |  | 0 | 127,481
Marketable Securities, Gross Unrealized Gains |  | 0 | 0
Marketable Securities, Gross Unrealized Losses |  | 0 | (753)
Marketable Securities, Fair Value |  | 0 | $ 126,728
Commercial notes (due within ninety days) |  |  |
Schedule Of Held To Maturity Securities And Marketable Securities [Line Items] |  |  |
Cash Equivalents, Cost Basis |  | 25,325 |
Cash Equivalents, Gross Unrealized Gains |  | 11 |
Cash Equivalents, Gross Unrealized Losses |  | 0 |
Cash Equivalents, Fair Value |  | $ 25,336 |

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