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Income Taxes - Additional Information (Details) - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2023 | Mar. 31, 2022
Income Tax Disclosure [Abstract] |  |
Percentage of investment company taxable income | 90.00% |
Percentage of investment company net tax exempt income | 90.00% |
Federal excise tax | $ 0.6 | $ 0.7

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- Definition Federal excise tax. + References No definition available. + Details
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- Definition Percentage of investment company net tax exempt income. + References No definition available. + Details
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- Definition Percentage of investment company taxable income. + References No definition available. + Details
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Namespace Prefix: | trin_
Data Type: | dtr-types:percentItemType
Balance Type: | na
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- References No definition available. + Details
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