Fiduciary Assets and Liabilities - Additional Information (Detail) - USD ($) $ in Millions |
Sep. 30, 2021 |
Dec. 31, 2020 |
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| Fiduciary Assets And Liabilities [Abstract] | ||
| Fiduciary liabilities current | $ 1,916.6 | $ 1,978.2 |
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- Definition Fiduciary assets and liabilities. No definition available.
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- Definition Fiduciary liabilities current. No definition available.
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