Investments in Marketable Securities - Gross Realized Gains and Losses from Sale of Available for Sale Securities (Detail) - USD ($) $ in Thousands |
12 Months Ended | ||
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Dec. 31, 2020 |
Dec. 31, 2019 |
Dec. 31, 2018 |
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| Investments, Debt and Equity Securities [Abstract] | |||
| Gross realized gains | $ 241 | $ 134 | $ 12 |
| Gross realized losses | $ (49) | $ (47) | $ (2) |
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- Definition This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. No definition available.
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- Definition This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. No definition available.
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- References No definition available.
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