Fair Value Measurements - Quantitative Information about Level 3 Fair Value Measurements (Details) $ in Millions	Dec. 31, 2020 USD ($)
Auction Rate Securities Owned
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Valuation Adjustment For Level Two and Three Assets	$ 5.0

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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