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Investments in Marketable Debt Securities, Available-for-Sale - Narrative (Detail) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2023 USD ($) security | Dec. 31, 2022
Schedule of Available-for-sale Securities [Line Items] |  |
Weighted average contractual maturity | 1 year 10 months 24 days | 1 year 1 month 6 days
Fitch, AA Rating | Moody's, Aaa Rating | Standard & Poor's, AA Rating |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Weighted average contractual maturity | 1 year 10 months 24 days |
Fitch, AA+ Rating | Moody's, Aa3 Rating | Standard & Poor's, AA+ Rating | Weighted Average Credit AA Plus Rating |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Available-for-sale, securities number of unrealized loss positions | security | 209 |
Available-for-sale, securities in unrealized loss positions, accumulated loss | $ | $ 4.1 |
Percentage of amortized cost | 2.00% |

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